diff --git a/app/engine/utils/FullTSLinearSeries.test.js b/app/engine/utils/FullTSLinearSeries.test.js
new file mode 100644
index 0000000..8b0153e
--- /dev/null
+++ b/app/engine/utils/FullTSLinearSeries.test.js
@@ -0,0 +1,268 @@
+'use strict'
+/*
+  Open Rowing Monitor, https://github.com/laberning/openrowingmonitor
+*/
+import { test } from 'uvu'
+import * as assert from 'uvu/assert'
+
+import { createTSLinearSeries } from './FullTSLinearSeries.js'
+
+test('Correct behaviour of a series after initialisation', () => {
+  const dataSeries = createTSLinearSeries(3)
+  testLength(dataSeries, 0)
+  testXAtSeriesBegin(dataSeries, 0)
+  testYAtSeriesBegin(dataSeries, 0)
+  testXAtSeriesEnd(dataSeries, 0)
+  testYAtSeriesEnd(dataSeries, 0)
+  testNumberOfXValuesAbove(dataSeries, 0, 0)
+  testNumberOfYValuesAbove(dataSeries, 0, 0)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfXValuesAbove(dataSeries, 10, 0)
+  testNumberOfYValuesAbove(dataSeries, 10, 0)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 10, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 10, 0)
+  testXSum(dataSeries, 0)
+  testYSum(dataSeries, 0)
+  testSlopeEquals(dataSeries, 0)
+  testInterceptEquals(dataSeries, 0)
+  testGoodnessOfFitEquals(dataSeries, 0)
+})
+
+test('Correct behaviour of a series after several puhed values, function y = 3x + 6, noisefree, 1 datapoint', () => {
+  const dataSeries = createTSLinearSeries(3)
+  testLength(dataSeries, 0)
+  dataSeries.push(5, 9)
+  testLength(dataSeries, 1)
+  testXAtSeriesBegin(dataSeries, 5)
+  testYAtSeriesBegin(dataSeries, 9)
+  testXAtSeriesEnd(dataSeries, 5)
+  testYAtSeriesEnd(dataSeries, 9)
+  testNumberOfXValuesAbove(dataSeries, 0, 1)
+  testNumberOfYValuesAbove(dataSeries, 0, 1)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfXValuesAbove(dataSeries, 10, 0)
+  testNumberOfYValuesAbove(dataSeries, 10, 0)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 10, 1)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 10, 1)
+  testXSum(dataSeries, 5)
+  testYSum(dataSeries, 9)
+  testSlopeEquals(dataSeries, 0)
+  testInterceptEquals(dataSeries, 0)
+  testGoodnessOfFitEquals(dataSeries, 0)
+})
+
+test('Correct behaviour of a series after several puhed values, function y = 3x + 6, noisefree, 2 datapoints', () => {
+  const dataSeries = createTSLinearSeries(3)
+  dataSeries.push(5, 9)
+  dataSeries.push(3, 3)
+  testLength(dataSeries, 2)
+  testXAtSeriesBegin(dataSeries, 5)
+  testYAtSeriesBegin(dataSeries, 9)
+  testXAtSeriesEnd(dataSeries, 3)
+  testYAtSeriesEnd(dataSeries, 3)
+  testNumberOfXValuesAbove(dataSeries, 0, 2)
+  testNumberOfYValuesAbove(dataSeries, 0, 2)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfXValuesAbove(dataSeries, 10, 0)
+  testNumberOfYValuesAbove(dataSeries, 10, 0)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 10, 2)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 10, 2)
+  testXSum(dataSeries, 8)
+  testYSum(dataSeries, 12)
+  testSlopeEquals(dataSeries, 3)
+  testInterceptEquals(dataSeries, -6)
+  testGoodnessOfFitEquals(dataSeries, 1)
+})
+
+test('Correct behaviour of a series after several puhed values, function y = 3x + 6, noisefree, 3 datapoints', () => {
+  const dataSeries = createTSLinearSeries(3)
+  dataSeries.push(5, 9)
+  dataSeries.push(3, 3)
+  dataSeries.push(4, 6)
+  testLength(dataSeries, 3)
+  testXAtSeriesBegin(dataSeries, 5)
+  testYAtSeriesBegin(dataSeries, 9)
+  testXAtSeriesEnd(dataSeries, 4)
+  testYAtSeriesEnd(dataSeries, 6)
+  testNumberOfXValuesAbove(dataSeries, 0, 3)
+  testNumberOfYValuesAbove(dataSeries, 0, 3)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfXValuesAbove(dataSeries, 10, 0)
+  testNumberOfYValuesAbove(dataSeries, 10, 0)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 10, 3)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 10, 3)
+  testXSum(dataSeries, 12)
+  testYSum(dataSeries, 18)
+  testSlopeEquals(dataSeries, 3)
+  testInterceptEquals(dataSeries, -6)
+  testGoodnessOfFitEquals(dataSeries, 1)
+})
+
+test('Correct behaviour of a series after several puhed values, function y = 3x + 6, noisefree, 4 datapoints', () => {
+  const dataSeries = createTSLinearSeries(3)
+  dataSeries.push(5, 9)
+  dataSeries.push(3, 3)
+  dataSeries.push(4, 6)
+  dataSeries.push(6, 12)
+  testLength(dataSeries, 3)
+  testXAtSeriesBegin(dataSeries, 3)
+  testYAtSeriesBegin(dataSeries, 3)
+  testXAtSeriesEnd(dataSeries, 6)
+  testYAtSeriesEnd(dataSeries, 12)
+  testNumberOfXValuesAbove(dataSeries, 0, 3)
+  testNumberOfYValuesAbove(dataSeries, 0, 3)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfXValuesAbove(dataSeries, 10, 0)
+  testNumberOfYValuesAbove(dataSeries, 10, 1)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 10, 3)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 10, 2)
+  testXSum(dataSeries, 13)
+  testYSum(dataSeries, 21)
+  testSlopeEquals(dataSeries, 3)
+  testInterceptEquals(dataSeries, -6)
+  testGoodnessOfFitEquals(dataSeries, 1)
+})
+
+test('Correct behaviour of a series after several puhed values, function y = 3x + 6, noisefree, 5 datapoints', () => {
+  const dataSeries = createTSLinearSeries(3)
+  dataSeries.push(5, 9)
+  dataSeries.push(3, 3)
+  dataSeries.push(4, 6)
+  dataSeries.push(6, 12)
+  dataSeries.push(1, -3)
+  testLength(dataSeries, 3)
+  testXAtSeriesBegin(dataSeries, 4)
+  testYAtSeriesBegin(dataSeries, 6)
+  testXAtSeriesEnd(dataSeries, 1)
+  testYAtSeriesEnd(dataSeries, -3)
+  testNumberOfXValuesAbove(dataSeries, 0, 3)
+  testNumberOfYValuesAbove(dataSeries, 0, 2)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 0, 1)
+  testNumberOfXValuesAbove(dataSeries, 10, 0)
+  testNumberOfYValuesAbove(dataSeries, 10, 1)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 10, 3)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 10, 2)
+  testXSum(dataSeries, 11)
+  testYSum(dataSeries, 15)
+  testSlopeEquals(dataSeries, 3)
+  testInterceptEquals(dataSeries, -6)
+  testGoodnessOfFitEquals(dataSeries, 1)
+})
+
+test('Correct behaviour of a series after several puhed values, function y = 3x + 6, noisefree, 4 datapoints and a reset', () => {
+  const dataSeries = createTSLinearSeries(3)
+  dataSeries.push(5, 9)
+  dataSeries.push(3, 3)
+  dataSeries.push(4, 6)
+  dataSeries.push(6, 12)
+  dataSeries.reset()
+  testLength(dataSeries, 0)
+  testXAtSeriesBegin(dataSeries, 0)
+  testYAtSeriesBegin(dataSeries, 0)
+  testXAtSeriesEnd(dataSeries, 0)
+  testYAtSeriesEnd(dataSeries, 0)
+  testNumberOfXValuesAbove(dataSeries, 0, 0)
+  testNumberOfYValuesAbove(dataSeries, 0, 0)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 0, 0)
+  testNumberOfXValuesAbove(dataSeries, 10, 0)
+  testNumberOfYValuesAbove(dataSeries, 10, 0)
+  testNumberOfXValuesEqualOrBelow(dataSeries, 10, 0)
+  testNumberOfYValuesEqualOrBelow(dataSeries, 10, 0)
+  testXSum(dataSeries, 0)
+  testYSum(dataSeries, 0)
+  testSlopeEquals(dataSeries, 0)
+  testInterceptEquals(dataSeries, 0)
+  testGoodnessOfFitEquals(dataSeries, 0)
+})
+
+test('Series with 5 elements, with 2 noisy datapoints', () => {
+  const dataSeries = createTSLinearSeries(5)
+  dataSeries.push(5, 9)
+  dataSeries.push(3, 2)
+  dataSeries.push(4, 7)
+  dataSeries.push(6, 12)
+  dataSeries.push(1, -3)
+  testSlopeBetween(dataSeries, 2.9, 3.1)
+  testInterceptBetween(dataSeries, -6.3, -5.8)
+  testGoodnessOfFitBetween(dataSeries, 0.9, 1.0)
+})
+
+function testLength (series, expectedValue) {
+  assert.ok(series.length() === expectedValue, `Expected length should be ${expectedValue}, encountered a ${series.length()}`)
+}
+
+function testXAtSeriesBegin (series, expectedValue) {
+  assert.ok(series.xAtSeriesBegin() === expectedValue, `Expected xAtSeriesBegin to be ${expectedValue}, encountered a ${series.xAtSeriesBegin()}`)
+}
+
+function testYAtSeriesBegin (series, expectedValue) {
+  assert.ok(series.yAtSeriesBegin() === expectedValue, `Expected yAtSeriesBegin to be ${expectedValue}, encountered a ${series.yAtSeriesBegin()}`)
+}
+
+function testXAtSeriesEnd (series, expectedValue) {
+  assert.ok(series.xAtSeriesEnd() === expectedValue, `Expected xAtSeriesEnd to be ${expectedValue}, encountered a ${series.xAtSeriesEnd()}`)
+}
+
+function testYAtSeriesEnd (series, expectedValue) {
+  assert.ok(series.yAtSeriesEnd() === expectedValue, `Expected yAtSeriesEnd to be ${expectedValue}, encountered a ${series.yAtSeriesEnd()}`)
+}
+
+function testNumberOfXValuesAbove (series, cutoff, expectedValue) {
+  assert.ok(series.numberOfXValuesAbove(cutoff) === expectedValue, `Expected numberOfXValuesAbove(${cutoff}) to be ${expectedValue}, encountered a ${series.numberOfXValuesAbove(cutoff)}`)
+}
+
+function testNumberOfYValuesAbove (series, cutoff, expectedValue) {
+  assert.ok(series.numberOfYValuesAbove(cutoff) === expectedValue, `Expected numberOfYValuesAbove(${cutoff}) to be ${expectedValue}, encountered a ${series.numberOfYValuesAbove(cutoff)}`)
+}
+
+function testNumberOfXValuesEqualOrBelow (series, cutoff, expectedValue) {
+  assert.ok(series.numberOfXValuesEqualOrBelow(cutoff) === expectedValue, `Expected numberOfXValuesEqualOrBelow(${cutoff}) to be ${expectedValue}, encountered a ${series.numberOfXValuesEqualOrBelow(cutoff)}`)
+}
+
+function testNumberOfYValuesEqualOrBelow (series, cutoff, expectedValue) {
+  assert.ok(series.numberOfYValuesEqualOrBelow(cutoff) === expectedValue, `Expected numberOfYValuesEqualOrBelow(${cutoff}) to be ${expectedValue}, encountered a ${series.numberOfYValuesEqualOrBelow(cutoff)}`)
+}
+
+function testXSum (series, expectedValue) {
+  assert.ok(series.xSum() === expectedValue, `Expected xSum to be ${expectedValue}, encountered a ${series.xSum()}`)
+}
+
+function testYSum (series, expectedValue) {
+  assert.ok(series.ySum() === expectedValue, `Expected ySum to be ${expectedValue}, encountered a ${series.ySum()}`)
+}
+
+function testSlopeEquals (series, expectedValue) {
+  assert.ok(series.slope() === expectedValue, `Expected slope to be ${expectedValue}, encountered a ${series.slope()}`)
+}
+
+function testSlopeBetween (series, expectedValueAbove, expectedValueBelow) {
+  assert.ok(series.slope() > expectedValueAbove, `Expected slope to be above ${expectedValueAbove}, encountered a ${series.slope()}`)
+  assert.ok(series.slope() < expectedValueBelow, `Expected slope to be below ${expectedValueBelow}, encountered a ${series.slope()}`)
+}
+
+function testInterceptEquals (series, expectedValue) {
+  assert.ok(series.intercept() === expectedValue, `Expected intercept to be ${expectedValue}, encountered ${series.intercept()}`)
+}
+
+function testInterceptBetween (series, expectedValueAbove, expectedValueBelow) {
+  assert.ok(series.intercept() > expectedValueAbove, `Expected intercept to be above ${expectedValueAbove}, encountered ${series.intercept()}`)
+  assert.ok(series.intercept() < expectedValueBelow, `Expected intercept to be below ${expectedValueBelow}, encountered ${series.intercept()}`)
+}
+
+function testGoodnessOfFitEquals (series, expectedValue) {
+  assert.ok(series.goodnessOfFit() === expectedValue, `Expected goodnessOfFit to be ${expectedValue}, encountered ${series.goodnessOfFit()}`)
+}
+
+function testGoodnessOfFitBetween (series, expectedValueAbove, expectedValueBelow) {
+  assert.ok(series.goodnessOfFit() > expectedValueAbove, `Expected goodnessOfFit to be above ${expectedValueAbove}, encountered ${series.goodnessOfFit()}`)
+  assert.ok(series.goodnessOfFit() < expectedValueBelow, `Expected goodnessOfFit to be below ${expectedValueBelow}, encountered ${series.goodnessOfFit()}`)
+}
+
+test.run()