diff --git a/README.md b/README.md
index 7a6265c..91c6484 100644
--- a/README.md
+++ b/README.md
@@ -139,7 +139,7 @@ The following list of strategies are currently supported by this package:
- [Chaikin Money Flow Strategy](strategy/volume/README.md#type-chaikinmoneyflowstrategy)
- Ease of Movement Strategy
-- Force Index Strategy
+- [Force Index Strategy](strategy/volume/README.md#type-forceindexstrategy)
- [Money Flow Index Strategy](strategy/volume/README.md#type-moneyflowindexstrategy)
- [Negative Volume Index Strategy](strategy/volume/README.md#type-negativevolumeindexstrategy)
- Volume Weighted Average Price Strategy
diff --git a/strategy/volume/README.md b/strategy/volume/README.md
index 4dfeb14..302b9b5 100644
--- a/strategy/volume/README.md
+++ b/strategy/volume/README.md
@@ -32,6 +32,12 @@ The information provided on this project is strictly for informational purposes
- [func \(c \*ChaikinMoneyFlowStrategy\) Compute\(snapshots \<\-chan \*asset.Snapshot\) \<\-chan strategy.Action](<#ChaikinMoneyFlowStrategy.Compute>)
- [func \(c \*ChaikinMoneyFlowStrategy\) Name\(\) string](<#ChaikinMoneyFlowStrategy.Name>)
- [func \(c \*ChaikinMoneyFlowStrategy\) Report\(snapshots \<\-chan \*asset.Snapshot\) \*helper.Report](<#ChaikinMoneyFlowStrategy.Report>)
+- [type ForceIndexStrategy](<#ForceIndexStrategy>)
+ - [func NewForceIndexStrategy\(\) \*ForceIndexStrategy](<#NewForceIndexStrategy>)
+ - [func NewForceIndexStrategyWith\(period int\) \*ForceIndexStrategy](<#NewForceIndexStrategyWith>)
+ - [func \(f \*ForceIndexStrategy\) Compute\(snapshots \<\-chan \*asset.Snapshot\) \<\-chan strategy.Action](<#ForceIndexStrategy.Compute>)
+ - [func \(f \*ForceIndexStrategy\) Name\(\) string](<#ForceIndexStrategy.Name>)
+ - [func \(f \*ForceIndexStrategy\) Report\(c \<\-chan \*asset.Snapshot\) \*helper.Report](<#ForceIndexStrategy.Report>)
- [type MoneyFlowIndexStrategy](<#MoneyFlowIndexStrategy>)
- [func NewMoneyFlowIndexStrategy\(\) \*MoneyFlowIndexStrategy](<#NewMoneyFlowIndexStrategy>)
- [func NewMoneyFlowIndexStrategyWith\(sellAt, buyAt float64\) \*MoneyFlowIndexStrategy](<#NewMoneyFlowIndexStrategyWith>)
@@ -135,6 +141,63 @@ func (c *ChaikinMoneyFlowStrategy) Report(snapshots <-chan *asset.Snapshot) *hel
Report function processes the provided asset snapshots and generates a report annotated with the recommended actions.
+
+## type [ForceIndexStrategy]()
+
+ForceIndexStrategy represents the configuration parameters for calculating the Force Index strategy. It recommends a Buy action when it crosses above zero, and a Sell action when it crosses below zero.
+
+```go
+type ForceIndexStrategy struct {
+ // ForceIndex is the Force Index instance.
+ ForceIndex *volume.Fi[float64]
+}
+```
+
+
+### func [NewForceIndexStrategy]()
+
+```go
+func NewForceIndexStrategy() *ForceIndexStrategy
+```
+
+NewForceIndexStrategy function initializes a new Force Index strategy instance with the default parameters.
+
+
+### func [NewForceIndexStrategyWith]()
+
+```go
+func NewForceIndexStrategyWith(period int) *ForceIndexStrategy
+```
+
+NewForceIndexStrategyWith function initializes a new Force Index strategy instance with the given parameters.
+
+
+### func \(\*ForceIndexStrategy\) [Compute]()
+
+```go
+func (f *ForceIndexStrategy) Compute(snapshots <-chan *asset.Snapshot) <-chan strategy.Action
+```
+
+Compute processes the provided asset snapshots and generates a stream of actionable recommendations.
+
+
+### func \(\*ForceIndexStrategy\) [Name]()
+
+```go
+func (f *ForceIndexStrategy) Name() string
+```
+
+Name returns the name of the strategy.
+
+
+### func \(\*ForceIndexStrategy\) [Report]()
+
+```go
+func (f *ForceIndexStrategy) Report(c <-chan *asset.Snapshot) *helper.Report
+```
+
+Report processes the provided asset snapshots and generates a report annotated with the recommended actions.
+
## type [MoneyFlowIndexStrategy]()
diff --git a/strategy/volume/force_index_strategy.go b/strategy/volume/force_index_strategy.go
new file mode 100644
index 0000000..01b5a1a
--- /dev/null
+++ b/strategy/volume/force_index_strategy.go
@@ -0,0 +1,111 @@
+// Copyright (c) 2021-2024 Onur Cinar.
+// The source code is provided under GNU AGPLv3 License.
+// https://github.com/cinar/indicator
+
+package volume
+
+import (
+ "fmt"
+
+ "github.com/cinar/indicator/v2/asset"
+ "github.com/cinar/indicator/v2/helper"
+ "github.com/cinar/indicator/v2/strategy"
+ "github.com/cinar/indicator/v2/volume"
+)
+
+// ForceIndexStrategy represents the configuration parameters for calculating the Force Index strategy.
+// It recommends a Buy action when it crosses above zero, and a Sell action when it crosses below zero.
+type ForceIndexStrategy struct {
+ // ForceIndex is the Force Index instance.
+ ForceIndex *volume.Fi[float64]
+}
+
+// NewForceIndexStrategy function initializes a new Force Index strategy instance with the default parameters.
+func NewForceIndexStrategy() *ForceIndexStrategy {
+ return NewForceIndexStrategyWith(
+ volume.DefaultFiPeriod,
+ )
+}
+
+// NewForceIndexStrategyWith function initializes a new Force Index strategy instance with the given parameters.
+func NewForceIndexStrategyWith(period int) *ForceIndexStrategy {
+ return &ForceIndexStrategy{
+ ForceIndex: volume.NewFiWithPeriod[float64](period),
+ }
+}
+
+// Name returns the name of the strategy.
+func (f *ForceIndexStrategy) Name() string {
+ return fmt.Sprintf("Force Index Strategy (%d)", f.ForceIndex.IdlePeriod()+1)
+}
+
+// Compute processes the provided asset snapshots and generates a stream of actionable recommendations.
+func (f *ForceIndexStrategy) Compute(snapshots <-chan *asset.Snapshot) <-chan strategy.Action {
+ snapshotsSplice := helper.Duplicate(snapshots, 2)
+
+ closings := asset.SnapshotsAsClosings(snapshotsSplice[0])
+ volumes := asset.SnapshotsAsVolumes(snapshotsSplice[1])
+
+ fis := f.ForceIndex.Compute(closings, volumes)
+
+ actions := helper.Map(fis, func(fi float64) strategy.Action {
+ if fi > 0 {
+ return strategy.Buy
+ }
+
+ if fi < 0 {
+ return strategy.Sell
+ }
+
+ return strategy.Hold
+ })
+
+ // Force Index starts only after a full period.
+ actions = helper.Shift(actions, f.ForceIndex.IdlePeriod(), strategy.Hold)
+
+ return actions
+}
+
+// Report processes the provided asset snapshots and generates a report annotated with the recommended actions.
+func (f *ForceIndexStrategy) Report(c <-chan *asset.Snapshot) *helper.Report {
+ //
+ // snapshots[0] -> dates
+ // snapshots[1] -> closings[0] -> closings
+ // closings[1] -> force index
+ // snapshots[2] -> volumes
+ // snapshots[3] -> actions -> annotations
+ // -> outcomes
+ //
+ snapshots := helper.Duplicate(c, 4)
+
+ dates := helper.Skip(asset.SnapshotsAsDates(snapshots[0]), f.ForceIndex.IdlePeriod())
+
+ closingsSplice := helper.Duplicate(
+ asset.SnapshotsAsClosings(snapshots[1]),
+ 2,
+ )
+ volumes := asset.SnapshotsAsVolumes(snapshots[2])
+
+ fis := f.ForceIndex.Compute(closingsSplice[0], volumes)
+
+ closingsSplice[1] = helper.Skip(closingsSplice[1], f.ForceIndex.IdlePeriod())
+
+ actions, outcomes := strategy.ComputeWithOutcome(f, snapshots[3])
+ actions = helper.Skip(actions, f.ForceIndex.IdlePeriod())
+ outcomes = helper.Skip(outcomes, f.ForceIndex.IdlePeriod())
+
+ annotations := strategy.ActionsToAnnotations(actions)
+ outcomes = helper.MultiplyBy(outcomes, 100)
+
+ report := helper.NewReport(f.Name(), dates)
+ report.AddChart()
+ report.AddChart()
+
+ report.AddColumn(helper.NewNumericReportColumn("Close", closingsSplice[1]))
+ report.AddColumn(helper.NewNumericReportColumn("Force Index", fis), 1)
+ report.AddColumn(helper.NewAnnotationReportColumn(annotations), 0, 1)
+
+ report.AddColumn(helper.NewNumericReportColumn("Outcome", outcomes), 2)
+
+ return report
+}
diff --git a/strategy/volume/force_index_strategy_test.go b/strategy/volume/force_index_strategy_test.go
new file mode 100644
index 0000000..3aade49
--- /dev/null
+++ b/strategy/volume/force_index_strategy_test.go
@@ -0,0 +1,55 @@
+// Copyright (c) 2021-2024 Onur Cinar.
+// The source code is provided under GNU AGPLv3 License.
+// https://github.com/cinar/indicator
+
+package volume_test
+
+import (
+ "os"
+ "testing"
+
+ "github.com/cinar/indicator/v2/asset"
+ "github.com/cinar/indicator/v2/helper"
+ "github.com/cinar/indicator/v2/strategy"
+ "github.com/cinar/indicator/v2/strategy/volume"
+)
+
+func TestForceIndexStrategy(t *testing.T) {
+ snapshots, err := helper.ReadFromCsvFile[asset.Snapshot]("testdata/brk-b.csv", true)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ results, err := helper.ReadFromCsvFile[strategy.Result]("testdata/force_index_strategy.csv", true)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ expected := helper.Map(results, func(r *strategy.Result) strategy.Action { return r.Action })
+
+ fis := volume.NewForceIndexStrategy()
+ actual := fis.Compute(snapshots)
+
+ err = helper.CheckEquals(actual, expected)
+ if err != nil {
+ t.Fatal(err)
+ }
+}
+
+func TestForceIndexStrategyReport(t *testing.T) {
+ snapshots, err := helper.ReadFromCsvFile[asset.Snapshot]("testdata/brk-b.csv", true)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ fis := volume.NewForceIndexStrategy()
+ report := fis.Report(snapshots)
+
+ fileName := "force_index_strategy.html"
+ defer os.Remove(fileName)
+
+ err = report.WriteToFile(fileName)
+ if err != nil {
+ t.Fatal(err)
+ }
+}
diff --git a/strategy/volume/testdata/force_index_strategy.csv b/strategy/volume/testdata/force_index_strategy.csv
new file mode 100644
index 0000000..a88dc23
--- /dev/null
+++ b/strategy/volume/testdata/force_index_strategy.csv
@@ -0,0 +1,252 @@
+Action
+0
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diff --git a/strategy/volume/volume.go b/strategy/volume/volume.go
index 55698f6..07d52aa 100644
--- a/strategy/volume/volume.go
+++ b/strategy/volume/volume.go
@@ -26,6 +26,7 @@ import (
func AllStrategies() []strategy.Strategy {
return []strategy.Strategy{
NewChaikinMoneyFlowStrategy(),
+ NewForceIndexStrategy(),
NewMoneyFlowIndexStrategy(),
NewNegativeVolumeIndexStrategy(),
}