diff --git a/Cargo.toml b/Cargo.toml
index 4a0fdda..19a3b29 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,9 @@
 [package]
 name = "traquer"
-version = "0.1.0"
+version = "0.0.1"
 edition = "2021"
+description = "statistical functions library"
+license = "Apache-2.0"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
@@ -14,5 +16,5 @@ serde_json = "*"
 criterion = "0.5.1"
 
 [[bench]]
-name = "my_benchmark"
+name = "traquer"
 harness = false
diff --git a/benches/my_benchmark.rs b/benches/traquer.rs
similarity index 95%
rename from benches/my_benchmark.rs
rename to benches/traquer.rs
index 52a4a54..d3c02cc 100644
--- a/benches/my_benchmark.rs
+++ b/benches/traquer.rs
@@ -33,7 +33,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     });
     c.bench_function("sig-twiggs", |b| {
         b.iter(|| {
-            black_box(indicator::twiggs(
+            black_box(volume::twiggs(
                 &stats.high,
                 &stats.low,
                 &stats.close,
@@ -47,7 +47,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     });
     c.bench_function("sig-kvo", |b| {
         b.iter(|| {
-            black_box(indicator::kvo(
+            black_box(volume::kvo(
                 &stats.high,
                 &stats.low,
                 &stats.close,
@@ -87,11 +87,11 @@ fn criterion_benchmark(c: &mut Criterion) {
         })
     });
     c.bench_function("sig-elder_force", |b| {
-        b.iter(|| black_box(indicator::elder_force(&stats.close, &stats.volume, 16)))
+        b.iter(|| black_box(volume::elder_force(&stats.close, &stats.volume, 16)))
     });
     c.bench_function("sig-mfi", |b| {
         b.iter(|| {
-            black_box(indicator::mfi(
+            black_box(volume::mfi(
                 &stats.high,
                 &stats.low,
                 &stats.close,
@@ -102,7 +102,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     });
     c.bench_function("sig-ad", |b| {
         b.iter(|| {
-            black_box(indicator::ad(
+            black_box(volume::ad(
                 &stats.high,
                 &stats.low,
                 &stats.close,
@@ -112,7 +112,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     });
     c.bench_function("sig-ad_yahoo", |b| {
         b.iter(|| {
-            black_box(indicator::ad_yahoo(
+            black_box(volume::ad_yahoo(
                 &stats.high,
                 &stats.low,
                 &stats.close,
@@ -122,7 +122,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     });
     c.bench_function("sig-cmf", |b| {
         b.iter(|| {
-            black_box(indicator::cmf(
+            black_box(volume::cmf(
                 &stats.high,
                 &stats.low,
                 &stats.close,
@@ -205,7 +205,7 @@ fn criterion_benchmark(c: &mut Criterion) {
         b.iter(|| black_box(indicator::tii(&stats.close, 16)))
     });
     c.bench_function("sig-tvi", |b| {
-        b.iter(|| black_box(indicator::tvi(&stats.close, &stats.volume, 0.5)))
+        b.iter(|| black_box(volume::tvi(&stats.close, &stats.volume, 0.5)))
     });
     c.bench_function("sig-supertrend", |b| {
         b.iter(|| {
diff --git a/src/indicator.rs b/src/indicator.rs
index 2246037..04704f8 100644
--- a/src/indicator.rs
+++ b/src/indicator.rs
@@ -2,42 +2,6 @@ use itertools::{izip, multiunzip};
 
 use crate::smooth;
 
-fn vforce(high: &[f64], low: &[f64], close: &[f64], volume: &[f64]) -> Vec<f64> {
-    izip!(&high[1..], &low[1..], &close[1..], &volume[1..])
-        .scan((high[0], low[0], close[0], 99), |state, (h, l, c, v)| {
-            let trend: i8 = {
-                if h + l + c > state.0 + state.1 + state.2 {
-                    1
-                } else {
-                    -1
-                }
-            };
-            *state = (*h, *l, *c, trend);
-            Some(v * trend as f64)
-        })
-        .collect::<Vec<f64>>()
-}
-
-/// klinger volume oscillator
-/// different from formula defined by https://www.investopedia.com/terms/k/klingeroscillator.asp
-pub fn kvo(
-    high: &[f64],
-    low: &[f64],
-    close: &[f64],
-    volume: &[f64],
-    short: usize,
-    long: usize,
-) -> Vec<f64> {
-    let vf = vforce(high, low, close, volume);
-    let short_ma = smooth::ewma(&vf, short);
-    let long_ma = smooth::ewma(&vf, long);
-    short_ma
-        .skip(long - short)
-        .zip(long_ma)
-        .map(|(x, y)| x - y)
-        .collect::<Vec<f64>>()
-}
-
 /// quick stick
 /// https://www.investopedia.com/terms/q/qstick.asp
 pub fn qstick(open: &[f64], close: &[f64], window: usize) -> Vec<f64> {
@@ -49,38 +13,6 @@ pub fn qstick(open: &[f64], close: &[f64], window: usize) -> Vec<f64> {
     smooth::ewma(&q, window).collect::<Vec<f64>>()
 }
 
-fn wilder_sum(data: &[f64], window: usize) -> impl Iterator<Item = f64> + '_ {
-    let initial = data[..(window - 1)].iter().sum::<f64>();
-    data[(window - 1)..].iter().scan(initial, move |state, x| {
-        let ma = *state * (window - 1) as f64 / window as f64 + x;
-        *state = ma;
-        Some(ma)
-    })
-}
-
-/// twiggs money flow
-/// https://www.marketvolume.com/technicalanalysis/twiggsmoneyflow.asp
-/// https://www.incrediblecharts.com/indicators/twiggs_money_flow.php
-pub fn twiggs(high: &[f64], low: &[f64], close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
-    let data = izip!(&high[1..], &low[1..], &close[1..], &volume[1..]);
-    // not using wilder moving average to minimise drift caused by floating point math
-    wilder_sum(
-        &data
-            .scan(close[0], |state, (h, l, c, vol)| {
-                let range_vol = vol
-                    * ((2.0 * c - f64::min(*l, *state) - f64::max(*h, *state))
-                        / (f64::max(*h, *state) - f64::min(*l, *state)));
-                *state = *c;
-                Some(range_vol)
-            })
-            .collect::<Vec<f64>>(),
-        window,
-    )
-    .zip(wilder_sum(&volume[1..], window))
-    .map(|(range, vol)| range / vol)
-    .collect()
-}
-
 /// shinohara intensity ratio
 /// https://www.sevendata.co.jp/shihyou/technical/shinohara.html
 pub fn shinohara(high: &[f64], low: &[f64], close: &[f64], period: usize) -> (Vec<f64>, Vec<f64>) {
@@ -209,38 +141,6 @@ pub fn cog(data: &[f64], window: usize) -> Vec<f64> {
         .collect::<Vec<f64>>()
 }
 
-/// accumulation/distribution
-/// https://www.investopedia.com/terms/a/accumulationdistribution.asp
-pub fn ad(high: &[f64], low: &[f64], close: &[f64], volume: &[f64]) -> Vec<f64> {
-    izip!(high, low, close, volume)
-        .scan(0.0, |state, (h, l, c, vol)| {
-            let mfm = ((c - l) - (h - c)) / (h - l);
-            let mfv = mfm * vol;
-            let adl = *state + mfv;
-            *state = adl;
-            Some(adl)
-        })
-        .collect::<Vec<f64>>()
-}
-
-/// accumulation/distribution
-/// like yahoo
-pub fn ad_yahoo(high: &[f64], low: &[f64], close: &[f64], volume: &[f64]) -> Vec<f64> {
-    izip!(&high[1..], &low[1..], &close[1..], &volume[1..])
-        .scan((close[0], 0.0), |state, (h, l, c, vol)| {
-            let mfm = if *c > state.0 {
-                c - f64::min(*l, state.0)
-            } else {
-                c - f64::max(*h, state.0)
-            };
-            let mfv = mfm * vol;
-            let adl = state.1 + mfv;
-            *state = (*c, adl);
-            Some(adl)
-        })
-        .collect::<Vec<f64>>()
-}
-
 /// elder ray
 /// https://www.investopedia.com/articles/trading/03/022603.asp
 /// returns tuple of bull power vec and bear power vec
@@ -255,59 +155,10 @@ pub fn elder_ray(high: &[f64], low: &[f64], close: &[f64], window: usize) -> (Ve
     .unzip()
 }
 
-/// elder force index
-/// https://www.investopedia.com/articles/trading/03/031203.asp
-pub fn elder_force(close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
-    smooth::ewma(
-        &izip!(&close[..close.len() - 1], &close[1..], &volume[1..])
-            .map(|(prev, curr, vol)| (curr - prev) * vol)
-            .collect::<Vec<f64>>(),
-        window,
-    )
-    .collect::<Vec<f64>>()
-}
-
 /// williams alligator
 /// https://www.investopedia.com/articles/trading/072115/exploring-williams-alligator-indicator.asp
 pub fn alligator(_data: &[f64]) {}
 
-/// money flow index
-/// https://www.investopedia.com/terms/m/mfi.asp
-pub fn mfi(high: &[f64], low: &[f64], close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
-    let (pos_mf, neg_mf): (Vec<f64>, Vec<f64>) =
-        izip!(&high[1..], &low[1..], &close[1..], &volume[1..])
-            .scan(
-                (high[0] + low[0] + close[0]) / 3.0,
-                |state, (h, l, c, vol)| {
-                    let hlc = (h + l + c) / 3.0;
-                    let pos_mf = if hlc > *state { hlc * vol } else { 0.0 };
-                    let neg_mf = if hlc < *state { hlc * vol } else { 0.0 };
-                    *state = hlc;
-                    Some((pos_mf, neg_mf))
-                },
-            )
-            .unzip();
-    pos_mf
-        .windows(window)
-        .zip(neg_mf.windows(window))
-        .map(|(pos, neg)| {
-            100.0 - (100.0 / (1.0 + pos.iter().sum::<f64>() / neg.iter().sum::<f64>()))
-        })
-        .collect::<Vec<f64>>()
-}
-
-/// chaikin money flow
-/// https://corporatefinanceinstitute.com/resources/equities/chaikin-money-flow-cmf/
-pub fn cmf(high: &[f64], low: &[f64], close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
-    izip!(high, low, close, volume)
-        .map(|(h, l, c, vol)| vol * ((c - l) - (h - c)) / (h - l))
-        .collect::<Vec<f64>>()
-        .windows(window)
-        .zip(volume.windows(window))
-        .map(|(mfv_win, v_win)| mfv_win.iter().sum::<f64>() / v_win.iter().sum::<f64>())
-        .collect::<Vec<f64>>()
-}
-
 /// chaikin volatility
 /// https://www.tradingview.com/chart/AUDUSD/gjfxqWqW-What-Is-a-Chaikin-Volatility-Indicator-in-Trading/
 /// https://theforexgeek.com/chaikins-volatility-indicator/
@@ -623,25 +474,6 @@ pub fn tii(data: &[f64], window: usize) -> Vec<f64> {
         .collect::<Vec<f64>>()
 }
 
-/// trade volume index
-/// https://www.investopedia.com/terms/t/tradevolumeindex.asp
-pub fn tvi(close: &[f64], volume: &[f64], min_tick: f64) -> Vec<f64> {
-    izip!(&close[..close.len() - 1], &close[1..], &volume[1..],)
-        .scan((1, 0.0), |state, (prev, curr, vol)| {
-            let direction = if curr - prev > min_tick {
-                1
-            } else if prev - curr > min_tick {
-                -1
-            } else {
-                state.0
-            };
-            let tvi = state.1 + direction as f64 * vol;
-            *state = (direction, tvi);
-            Some(tvi)
-        })
-        .collect::<Vec<f64>>()
-}
-
 /// supertrend
 /// https://www.tradingview.com/support/solutions/43000634738-supertrend/
 /// https://www.investopedia.com/supertrend-indicator-7976167
@@ -727,7 +559,7 @@ fn _stc(series: &[f64], window: usize) -> Vec<f64> {
     .collect::<Vec<f64>>()
 }
 
-/// Shaff Trend Cycle
+/// Schaff Trend Cycle
 /// https://www.investopedia.com/articles/forex/10/schaff-trend-cycle-indicator.asp
 /// https://www.stockmaniacs.net/schaff-trend-cycle-indicator/
 pub fn stc(close: &[f64], window: usize, short: usize, long: usize) -> Vec<f64> {
diff --git a/src/lib.rs b/src/lib.rs
index f733640..a11b0f6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -4,3 +4,4 @@
 
 pub mod indicator;
 pub mod smooth;
+pub mod volume;
diff --git a/src/volume.rs b/src/volume.rs
new file mode 100644
index 0000000..ccf8b34
--- /dev/null
+++ b/src/volume.rs
@@ -0,0 +1,171 @@
+use itertools::izip;
+
+use crate::smooth;
+
+fn vforce(high: &[f64], low: &[f64], close: &[f64], volume: &[f64]) -> Vec<f64> {
+    izip!(&high[1..], &low[1..], &close[1..], &volume[1..])
+        .scan((high[0], low[0], close[0], 99), |state, (h, l, c, v)| {
+            let trend: i8 = {
+                if h + l + c > state.0 + state.1 + state.2 {
+                    1
+                } else {
+                    -1
+                }
+            };
+            *state = (*h, *l, *c, trend);
+            Some(v * trend as f64)
+        })
+        .collect::<Vec<f64>>()
+}
+
+/// klinger volume oscillator
+/// different from formula defined by https://www.investopedia.com/terms/k/klingeroscillator.asp
+pub fn kvo(
+    high: &[f64],
+    low: &[f64],
+    close: &[f64],
+    volume: &[f64],
+    short: usize,
+    long: usize,
+) -> Vec<f64> {
+    let vf = vforce(high, low, close, volume);
+    let short_ma = smooth::ewma(&vf, short);
+    let long_ma = smooth::ewma(&vf, long);
+    short_ma
+        .skip(long - short)
+        .zip(long_ma)
+        .map(|(x, y)| x - y)
+        .collect::<Vec<f64>>()
+}
+
+fn wilder_sum(data: &[f64], window: usize) -> impl Iterator<Item = f64> + '_ {
+    let initial = data[..(window - 1)].iter().sum::<f64>();
+    data[(window - 1)..].iter().scan(initial, move |state, x| {
+        let ma = *state * (window - 1) as f64 / window as f64 + x;
+        *state = ma;
+        Some(ma)
+    })
+}
+
+/// twiggs money flow
+/// https://www.marketvolume.com/technicalanalysis/twiggsmoneyflow.asp
+/// https://www.incrediblecharts.com/indicators/twiggs_money_flow.php
+pub fn twiggs(high: &[f64], low: &[f64], close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
+    let data = izip!(&high[1..], &low[1..], &close[1..], &volume[1..]);
+    // not using wilder moving average to minimise drift caused by floating point math
+    wilder_sum(
+        &data
+            .scan(close[0], |state, (h, l, c, vol)| {
+                let range_vol = vol
+                    * ((2.0 * c - f64::min(*l, *state) - f64::max(*h, *state))
+                        / (f64::max(*h, *state) - f64::min(*l, *state)));
+                *state = *c;
+                Some(range_vol)
+            })
+            .collect::<Vec<f64>>(),
+        window,
+    )
+    .zip(wilder_sum(&volume[1..], window))
+    .map(|(range, vol)| range / vol)
+    .collect()
+}
+
+/// accumulation/distribution
+/// https://www.investopedia.com/terms/a/accumulationdistribution.asp
+pub fn ad(high: &[f64], low: &[f64], close: &[f64], volume: &[f64]) -> Vec<f64> {
+    izip!(high, low, close, volume)
+        .scan(0.0, |state, (h, l, c, vol)| {
+            let mfm = ((c - l) - (h - c)) / (h - l);
+            let mfv = mfm * vol;
+            let adl = *state + mfv;
+            *state = adl;
+            Some(adl)
+        })
+        .collect::<Vec<f64>>()
+}
+
+/// accumulation/distribution
+/// like yahoo
+pub fn ad_yahoo(high: &[f64], low: &[f64], close: &[f64], volume: &[f64]) -> Vec<f64> {
+    izip!(&high[1..], &low[1..], &close[1..], &volume[1..])
+        .scan((close[0], 0.0), |state, (h, l, c, vol)| {
+            let mfm = if *c > state.0 {
+                c - f64::min(*l, state.0)
+            } else {
+                c - f64::max(*h, state.0)
+            };
+            let mfv = mfm * vol;
+            let adl = state.1 + mfv;
+            *state = (*c, adl);
+            Some(adl)
+        })
+        .collect::<Vec<f64>>()
+}
+
+/// elder force index
+/// https://www.investopedia.com/articles/trading/03/031203.asp
+pub fn elder_force(close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
+    smooth::ewma(
+        &izip!(&close[..close.len() - 1], &close[1..], &volume[1..])
+            .map(|(prev, curr, vol)| (curr - prev) * vol)
+            .collect::<Vec<f64>>(),
+        window,
+    )
+    .collect::<Vec<f64>>()
+}
+
+/// money flow index
+/// https://www.investopedia.com/terms/m/mfi.asp
+pub fn mfi(high: &[f64], low: &[f64], close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
+    let (pos_mf, neg_mf): (Vec<f64>, Vec<f64>) =
+        izip!(&high[1..], &low[1..], &close[1..], &volume[1..])
+            .scan(
+                (high[0] + low[0] + close[0]) / 3.0,
+                |state, (h, l, c, vol)| {
+                    let hlc = (h + l + c) / 3.0;
+                    let pos_mf = if hlc > *state { hlc * vol } else { 0.0 };
+                    let neg_mf = if hlc < *state { hlc * vol } else { 0.0 };
+                    *state = hlc;
+                    Some((pos_mf, neg_mf))
+                },
+            )
+            .unzip();
+    pos_mf
+        .windows(window)
+        .zip(neg_mf.windows(window))
+        .map(|(pos, neg)| {
+            100.0 - (100.0 / (1.0 + pos.iter().sum::<f64>() / neg.iter().sum::<f64>()))
+        })
+        .collect::<Vec<f64>>()
+}
+
+/// chaikin money flow
+/// https://corporatefinanceinstitute.com/resources/equities/chaikin-money-flow-cmf/
+pub fn cmf(high: &[f64], low: &[f64], close: &[f64], volume: &[f64], window: usize) -> Vec<f64> {
+    izip!(high, low, close, volume)
+        .map(|(h, l, c, vol)| vol * ((c - l) - (h - c)) / (h - l))
+        .collect::<Vec<f64>>()
+        .windows(window)
+        .zip(volume.windows(window))
+        .map(|(mfv_win, v_win)| mfv_win.iter().sum::<f64>() / v_win.iter().sum::<f64>())
+        .collect::<Vec<f64>>()
+}
+
+/// trade volume index
+/// https://www.investopedia.com/terms/t/tradevolumeindex.asp
+pub fn tvi(close: &[f64], volume: &[f64], min_tick: f64) -> Vec<f64> {
+    izip!(&close[..close.len() - 1], &close[1..], &volume[1..],)
+        .scan((1, 0.0), |state, (prev, curr, vol)| {
+            let direction = if curr - prev > min_tick {
+                1
+            } else if prev - curr > min_tick {
+                -1
+            } else {
+                state.0
+            };
+            let tvi = state.1 + direction as f64 * vol;
+            *state = (direction, tvi);
+            Some(tvi)
+        })
+        .collect::<Vec<f64>>()
+}
diff --git a/tests/indicator_test.rs b/tests/indicator_test.rs
index 47f00eb..f65c032 100644
--- a/tests/indicator_test.rs
+++ b/tests/indicator_test.rs
@@ -108,35 +108,6 @@ fn test_qstick() {
     );
 }
 
-#[test]
-fn test_twiggs() {
-    let stats = common::test_data();
-    let result = indicator::twiggs(&stats.high, &stats.low, &stats.close, &stats.volume, 16);
-    assert_eq!(
-        vec![
-            -0.18613223690613337,
-            -0.19317352339707441,
-            -0.17453508236798282,
-            -0.18375940487028466,
-            -0.17502586620511137,
-            -0.17382219844626962,
-            -0.17255131614049954,
-            -0.1640328604291291,
-            -0.1420920809902787,
-            -0.1527562191185741,
-            -0.16523607317121108,
-            -0.16430836437056545,
-            -0.15920358586187838,
-            -0.16715044705529314,
-            -0.1621303949690616,
-            -0.11881583358526457,
-            -0.14855035203055256,
-            -0.15469018900758857,
-        ],
-        result
-    );
-}
-
 #[test]
 fn test_rsi() {
     let stats = common::test_data();
@@ -166,35 +137,6 @@ fn test_rsi() {
     );
 }
 
-#[test]
-fn test_kvo() {
-    let stats = common::test_data();
-    let result = indicator::kvo(&stats.high, &stats.low, &stats.close, &stats.volume, 10, 16);
-    assert_eq!(
-        vec![
-            -656322.9297191856,
-            -713366.2205723817,
-            -454503.008716189,
-            -242243.40638757526,
-            -150673.24628108775,
-            -51176.64414472319,
-            -14990.826684893807,
-            -172705.0049532547,
-            -10141.336752269068,
-            101922.08867095085,
-            -103711.73979187862,
-            -34908.10280425532,
-            64722.50363716809,
-            -92755.34740538022,
-            7627.067027119803,
-            344638.3915205905,
-            1045791.2002935112,
-            491703.71571153356,
-        ],
-        result
-    );
-}
-
 #[test]
 fn test_macd() {
     let stats = common::test_data();
@@ -361,182 +303,6 @@ fn test_elder_ray() {
     );
 }
 
-#[test]
-fn test_elder_force() {
-    let stats = common::test_data();
-    let result = indicator::elder_force(&stats.close, &stats.volume, 16);
-    assert_eq!(
-        vec![
-            15163924.326658249,
-            12880758.096563116,
-            12050605.61114628,
-            10383051.49386349,
-            9364365.879667005,
-            8442213.142258454,
-            7502743.65895507,
-            6497707.801010304,
-            6702367.440261993,
-            6181683.142965115,
-            5074974.977031417,
-            4748656.497570231,
-            4696379.1776512945,
-            3995675.78829447,
-            3931504.90271624,
-            4298754.639673724,
-            6967489.387947403,
-            5483494.728818839,
-        ],
-        result
-    );
-}
-#[test]
-fn test_mfi() {
-    let stats = common::test_data();
-    let result = indicator::mfi(&stats.high, &stats.low, &stats.close, &stats.volume, 16);
-    assert_eq!(
-        vec![
-            57.23427292919309,
-            47.90601255639084,
-            21.137944754987743,
-            30.26117456879261,
-            38.51678304832031,
-            50.513828792387955,
-            40.49727451951461,
-            44.32715297759769,
-            53.90985418627666,
-            53.60555590702833,
-            55.07839144768625,
-            60.65330461162574,
-            70.80167748372554,
-            64.11003122868968,
-            70.5203113367536,
-            82.33336948811267,
-            87.34401989374501,
-            85.51147984689622,
-        ],
-        result,
-    );
-}
-
-#[test]
-fn test_ad() {
-    let stats = common::test_data();
-    let result = indicator::ad(&stats.high, &stats.low, &stats.close, &stats.volume);
-    assert_eq!(
-        vec![
-            -12220014.53999535,
-            5594494.456558675,
-            -18251656.973511968,
-            -27192954.017261956,
-            -38906280.775514156,
-            -43519171.793909825,
-            -36388813.33166392,
-            -40306772.321005546,
-            -43038979.11826538,
-            -41295751.02899514,
-            -42530068.87440958,
-            -44631518.28622454,
-            -47863110.10330983,
-            -47175528.73291944,
-            -48928369.757053,
-            -51464869.93675375,
-            -50970834.60616014,
-            -52061872.3366441,
-            -50169605.03257219,
-            -51716854.467872486,
-            -50995298.79832875,
-            -51206859.811250634,
-            -51316121.96369292,
-            -50145740.751600124,
-            -48579440.279196754,
-            -50497562.83272522,
-            -51860185.667756006,
-            -52138562.67733089,
-            -52113820.167047076,
-            -52915683.21006013,
-            -52969956.24185295,
-            -50690564.9792013,
-            -55780759.43377636,
-            -56496069.02735695,
-        ],
-        result
-    );
-}
-
-#[test]
-fn test_ad_yahoo() {
-    let stats = common::test_data();
-    let result = indicator::ad_yahoo(&stats.high, &stats.low, &stats.close, &stats.volume);
-    assert_eq!(
-        vec![
-            336703421.3851929,
-            524311079.90493774,
-            386249980.45578,
-            279963693.60809326,
-            236454248.4260559,
-            297360960.63041687,
-            276863635.63041687,
-            264624868.58329773,
-            273054631.709671,
-            264990289.9585724,
-            259319809.13619995,
-            246661018.79997253,
-            257403780.75141907,
-            252853500.13084412,
-            245025403.5522461,
-            248117583.03375244,
-            243874594.40460205,
-            253856117.67807007,
-            246398220.74928284,
-            248672416.60499573,
-            250625005.75447083,
-            251593806.81037903,
-            250553745.6768036,
-            258791060.41145325,
-            261067611.32469177,
-            257009643.54515076,
-            259310911.44676208,
-            263993610.364151,
-            261545710.7322693,
-            264995933.9931488,
-            277479333.9931488,
-            304462333.9931488,
-            298815868.7785034,
-        ],
-        result
-    );
-}
-
-#[test]
-fn test_cmf() {
-    let stats = common::test_data();
-    let result = indicator::cmf(&stats.high, &stats.low, &stats.close, &stats.volume, 16);
-    assert_eq!(
-        vec![
-            -0.31996402726557827,
-            -0.26431568287267065,
-            -0.4636131359961498,
-            -0.3495321537587002,
-            -0.3266108255947919,
-            -0.18899633112243233,
-            -0.14523458977952866,
-            -0.3326493878867275,
-            -0.23687295947927223,
-            -0.13961905719447967,
-            -0.23334715737003828,
-            -0.2421809194283885,
-            -0.19835662209432817,
-            -0.11853261789898396,
-            -0.1750773026968712,
-            -0.12288304498976765,
-            0.021699608427354102,
-            -0.1013140453290804,
-            -0.09237139625802167,
-        ],
-        result
-    );
-}
-
 #[test]
 fn test_cvi() {
     let stats = common::test_data();
@@ -1082,22 +848,6 @@ fn test_tii_odd() {
     );
 }
 
-#[test]
-fn test_tvi() {
-    let stats = common::test_data();
-    let result = indicator::tvi(&stats.close, &stats.volume, 0.5);
-    assert_eq!(
-        vec![
-            24398800.0, 59729800.0, 40971500.0, 28363400.0, 15375500.0, 24818400.0, 19995500.0,
-            15377100.0, 18304100.0, 15642600.0, 13365300.0, 9015200.0, 13278200.0, 11264800.0,
-            7816300.0, 9515300.0, 7361500.0, 9645600.0, 7117500.0, 8603900.0, 10560400.0,
-            11944400.0, 10458600.0, 13222800.0, 15901100.0, 14148200.0, 15746300.0, 18111300.0,
-            16923000.0, 19039700.0, 25281400.0, 38772900.0, 36090498.0,
-        ],
-        result
-    );
-}
-
 #[test]
 fn test_supertrend() {
     let stats = common::test_data();
diff --git a/tests/volume_test.rs b/tests/volume_test.rs
new file mode 100644
index 0000000..b64dbca
--- /dev/null
+++ b/tests/volume_test.rs
@@ -0,0 +1,253 @@
+use traquer::volume;
+
+mod common;
+
+#[test]
+fn test_twiggs() {
+    let stats = common::test_data();
+    let result = volume::twiggs(&stats.high, &stats.low, &stats.close, &stats.volume, 16);
+    assert_eq!(
+        vec![
+            -0.18613223690613337,
+            -0.19317352339707441,
+            -0.17453508236798282,
+            -0.18375940487028466,
+            -0.17502586620511137,
+            -0.17382219844626962,
+            -0.17255131614049954,
+            -0.1640328604291291,
+            -0.1420920809902787,
+            -0.1527562191185741,
+            -0.16523607317121108,
+            -0.16430836437056545,
+            -0.15920358586187838,
+            -0.16715044705529314,
+            -0.1621303949690616,
+            -0.11881583358526457,
+            -0.14855035203055256,
+            -0.15469018900758857,
+        ],
+        result
+    );
+}
+
+#[test]
+fn test_kvo() {
+    let stats = common::test_data();
+    let result = volume::kvo(&stats.high, &stats.low, &stats.close, &stats.volume, 10, 16);
+    assert_eq!(
+        vec![
+            -656322.9297191856,
+            -713366.2205723817,
+            -454503.008716189,
+            -242243.40638757526,
+            -150673.24628108775,
+            -51176.64414472319,
+            -14990.826684893807,
+            -172705.0049532547,
+            -10141.336752269068,
+            101922.08867095085,
+            -103711.73979187862,
+            -34908.10280425532,
+            64722.50363716809,
+            -92755.34740538022,
+            7627.067027119803,
+            344638.3915205905,
+            1045791.2002935112,
+            491703.71571153356,
+        ],
+        result
+    );
+}
+
+#[test]
+fn test_elder_force() {
+    let stats = common::test_data();
+    let result = volume::elder_force(&stats.close, &stats.volume, 16);
+    assert_eq!(
+        vec![
+            15163924.326658249,
+            12880758.096563116,
+            12050605.61114628,
+            10383051.49386349,
+            9364365.879667005,
+            8442213.142258454,
+            7502743.65895507,
+            6497707.801010304,
+            6702367.440261993,
+            6181683.142965115,
+            5074974.977031417,
+            4748656.497570231,
+            4696379.1776512945,
+            3995675.78829447,
+            3931504.90271624,
+            4298754.639673724,
+            6967489.387947403,
+            5483494.728818839,
+        ],
+        result
+    );
+}
+#[test]
+fn test_mfi() {
+    let stats = common::test_data();
+    let result = volume::mfi(&stats.high, &stats.low, &stats.close, &stats.volume, 16);
+    assert_eq!(
+        vec![
+            57.23427292919309,
+            47.90601255639084,
+            21.137944754987743,
+            30.26117456879261,
+            38.51678304832031,
+            50.513828792387955,
+            40.49727451951461,
+            44.32715297759769,
+            53.90985418627666,
+            53.60555590702833,
+            55.07839144768625,
+            60.65330461162574,
+            70.80167748372554,
+            64.11003122868968,
+            70.5203113367536,
+            82.33336948811267,
+            87.34401989374501,
+            85.51147984689622,
+        ],
+        result,
+    );
+}
+
+#[test]
+fn test_ad() {
+    let stats = common::test_data();
+    let result = volume::ad(&stats.high, &stats.low, &stats.close, &stats.volume);
+    assert_eq!(
+        vec![
+            -12220014.53999535,
+            5594494.456558675,
+            -18251656.973511968,
+            -27192954.017261956,
+            -38906280.775514156,
+            -43519171.793909825,
+            -36388813.33166392,
+            -40306772.321005546,
+            -43038979.11826538,
+            -41295751.02899514,
+            -42530068.87440958,
+            -44631518.28622454,
+            -47863110.10330983,
+            -47175528.73291944,
+            -48928369.757053,
+            -51464869.93675375,
+            -50970834.60616014,
+            -52061872.3366441,
+            -50169605.03257219,
+            -51716854.467872486,
+            -50995298.79832875,
+            -51206859.811250634,
+            -51316121.96369292,
+            -50145740.751600124,
+            -48579440.279196754,
+            -50497562.83272522,
+            -51860185.667756006,
+            -52138562.67733089,
+            -52113820.167047076,
+            -52915683.21006013,
+            -52969956.24185295,
+            -50690564.9792013,
+            -55780759.43377636,
+            -56496069.02735695,
+        ],
+        result
+    );
+}
+
+#[test]
+fn test_ad_yahoo() {
+    let stats = common::test_data();
+    let result = volume::ad_yahoo(&stats.high, &stats.low, &stats.close, &stats.volume);
+    assert_eq!(
+        vec![
+            336703421.3851929,
+            524311079.90493774,
+            386249980.45578,
+            279963693.60809326,
+            236454248.4260559,
+            297360960.63041687,
+            276863635.63041687,
+            264624868.58329773,
+            273054631.709671,
+            264990289.9585724,
+            259319809.13619995,
+            246661018.79997253,
+            257403780.75141907,
+            252853500.13084412,
+            245025403.5522461,
+            248117583.03375244,
+            243874594.40460205,
+            253856117.67807007,
+            246398220.74928284,
+            248672416.60499573,
+            250625005.75447083,
+            251593806.81037903,
+            250553745.6768036,
+            258791060.41145325,
+            261067611.32469177,
+            257009643.54515076,
+            259310911.44676208,
+            263993610.364151,
+            261545710.7322693,
+            264995933.9931488,
+            277479333.9931488,
+            304462333.9931488,
+            298815868.7785034,
+        ],
+        result
+    );
+}
+
+#[test]
+fn test_cmf() {
+    let stats = common::test_data();
+    let result = volume::cmf(&stats.high, &stats.low, &stats.close, &stats.volume, 16);
+    assert_eq!(
+        vec![
+            -0.31996402726557827,
+            -0.26431568287267065,
+            -0.4636131359961498,
+            -0.3495321537587002,
+            -0.3266108255947919,
+            -0.18899633112243233,
+            -0.14523458977952866,
+            -0.3326493878867275,
+            -0.23687295947927223,
+            -0.13961905719447967,
+            -0.23334715737003828,
+            -0.2421809194283885,
+            -0.19835662209432817,
+            -0.11853261789898396,
+            -0.1750773026968712,
+            -0.12288304498976765,
+            0.021699608427354102,
+            -0.1013140453290804,
+            -0.09237139625802167,
+        ],
+        result
+    );
+}
+
+#[test]
+fn test_tvi() {
+    let stats = common::test_data();
+    let result = volume::tvi(&stats.close, &stats.volume, 0.5);
+    assert_eq!(
+        vec![
+            24398800.0, 59729800.0, 40971500.0, 28363400.0, 15375500.0, 24818400.0, 19995500.0,
+            15377100.0, 18304100.0, 15642600.0, 13365300.0, 9015200.0, 13278200.0, 11264800.0,
+            7816300.0, 9515300.0, 7361500.0, 9645600.0, 7117500.0, 8603900.0, 10560400.0,
+            11944400.0, 10458600.0, 13222800.0, 15901100.0, 14148200.0, 15746300.0, 18111300.0,
+            16923000.0, 19039700.0, 25281400.0, 38772900.0, 36090498.0,
+        ],
+        result
+    );
+}