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diff --git a/spec/frontend/analytics/instance_statistics/utils_spec.js b/spec/frontend/analytics/instance_statistics/utils_spec.js
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+++ b/spec/frontend/analytics/instance_statistics/utils_spec.js
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+import {
+  getAverageByMonth,
+  extractValues,
+  sortByDate,
+} from '~/analytics/instance_statistics/utils';
+import {
+  mockCountsData1,
+  mockCountsData2,
+  countsMonthlyChartData1,
+  countsMonthlyChartData2,
+} from './mock_data';
+
+describe('getAverageByMonth', () => {
+  it('collects data into average by months', () => {
+    expect(getAverageByMonth(mockCountsData1)).toStrictEqual(countsMonthlyChartData1);
+    expect(getAverageByMonth(mockCountsData2)).toStrictEqual(countsMonthlyChartData2);
+  });
+
+  it('it transforms a data point to the first of the month', () => {
+    const item = mockCountsData1[0];
+    const firstOfTheMonth = item.recordedAt.replace(/-[0-9]{2}$/, '-01');
+    expect(getAverageByMonth([item])).toStrictEqual([[firstOfTheMonth, item.count]]);
+  });
+
+  it('it uses sane defaults', () => {
+    expect(getAverageByMonth()).toStrictEqual([]);
+  });
+
+  it('it errors when passing null', () => {
+    expect(() => {
+      getAverageByMonth(null);
+    }).toThrow();
+  });
+
+  describe('when shouldRound = true', () => {
+    const options = { shouldRound: true };
+
+    it('rounds the averages', () => {
+      const roundedData1 = countsMonthlyChartData1.map(([date, avg]) => [date, Math.round(avg)]);
+      const roundedData2 = countsMonthlyChartData2.map(([date, avg]) => [date, Math.round(avg)]);
+      expect(getAverageByMonth(mockCountsData1, options)).toStrictEqual(roundedData1);
+      expect(getAverageByMonth(mockCountsData2, options)).toStrictEqual(roundedData2);
+    });
+  });
+});
+
+describe('extractValues', () => {
+  it('extracts only requested values', () => {
+    const data = { fooBar: { baz: 'quis' }, ignored: 'ignored' };
+    expect(extractValues(data, ['fooBar'], 'foo', 'baz')).toEqual({ bazBar: 'quis' });
+  });
+
+  it('is able to extract multiple values', () => {
+    const data = {
+      fooBar: { baz: 'quis' },
+      fooBaz: { baz: 'quis' },
+      fooQuis: { baz: 'quis' },
+    };
+    expect(extractValues(data, ['fooBar', 'fooBaz', 'fooQuis'], 'foo', 'baz')).toEqual({
+      bazBar: 'quis',
+      bazBaz: 'quis',
+      bazQuis: 'quis',
+    });
+  });
+
+  it('returns empty data set when keys are not found', () => {
+    const data = { foo: { baz: 'quis' }, ignored: 'ignored' };
+    expect(extractValues(data, ['fooBar'], 'foo', 'baz')).toEqual({});
+  });
+
+  it('returns empty data when params are missing', () => {
+    expect(extractValues()).toEqual({});
+  });
+});
+
+describe('sortByDate', () => {
+  it('sorts the array by date', () => {
+    expect(sortByDate(mockCountsData1)).toStrictEqual([...mockCountsData1].reverse());
+  });
+
+  it('does not modify the original array', () => {
+    expect(sortByDate(countsMonthlyChartData1)).not.toBe(countsMonthlyChartData1);
+  });
+});