diff --git a/index.js b/index.js
index f7bf7d9..8fe33cf 100644
--- a/index.js
+++ b/index.js
@@ -67,10 +67,10 @@ async function add_run (runs_dir, chunks_dir, date) {
     await write_compressed(`./${runs_dir}/${date}.xz`, new_run)
 }
 
-async function recalc_scores (runs_dir) {
-    console.log(`Calculating scores for ${runs_dir} directory...`)
+async function recalc_detailed_scores (runs_dir) {
+    console.log(`Calculating detailed scores for ${runs_dir} directory...`)
 
-    const scores = []
+    const result = []
     console.log('Enumerating runs')
     const all_runs = await all_runs_sorted(runs_dir)
     const run_count = all_runs.length
@@ -85,19 +85,34 @@ async function recalc_scores (runs_dir) {
         const run = await read_compressed(`./${runs_dir}/${r}`)
         console.log(`Calculating score for run ${runs_dir}/${r} (${i}/${run_count})`)
         const score = score_run(run, new_run, test_to_areas)
-        const row = [
+        result.push({
             date,
-            run.run_info.revision.substring(0, 9),
-            run.run_info.browser_version
-        ]
+            revision: run.run_info.revision.substring(0, 9),
+            browser_version: run.run_info.browser_version,
+            area_scores: area_keys.map(area => score[area]),
+        })
+    }
+
+    return result
+}
+
+function generate_rows (detailed_scores) {
+    const result = []
 
-        for (const area of area_keys) {
-            row.push(score[area])
+    const { area_keys } = get_focus_areas()
+    for (const score of detailed_scores) {
+        const row = [
+            score.date,
+            score.revision,
+            score.browser_version,
+        ]
+        for (const area_score of score.area_scores) {
+            row.push(area_score.per_mille)
         }
-        scores.push(row)
+        result.push(row)
     }
 
-    return scores
+    return result
 }
 
 async function main () {
@@ -114,10 +129,16 @@ async function main () {
         await add_run('runs-2020', chunks_2020, date)
     }
 
-    const scores_2013 = await recalc_scores('runs')
-    const scores_2020 = await recalc_scores('runs-2020')
-    const scores_by_date = new Map(scores_2020.map(score => [score[0], score]))
+    const detailed_scores_2013 = await recalc_detailed_scores('runs')
+    const detailed_scores_2020 = await recalc_detailed_scores('runs-2020')
+    const detailed_scores = {
+        layout_2013: detailed_scores_2013,
+        layout_2020: detailed_scores_2020,
+    }
 
+    const scores_2013 = generate_rows(detailed_scores_2013)
+    const scores_2020 = generate_rows(detailed_scores_2020)
+    const scores_by_date = new Map(scores_2020.map(score => [score[0], score]))
     const scores = []
     for (const score_2013 of scores_2013) {
         const len = scores.push(score_2013)
@@ -131,7 +152,12 @@ async function main () {
 
     console.log('Writing site/scores.json')
     write_json_file(
-        './site/scores.json', { area_keys, focus_areas, scores })
+        './site/scores.json', {
+            area_keys,
+            focus_areas,
+            scores,
+            detailed_scores,
+        })
 
     console.log('Done')
 }
diff --git a/process-wpt-results.js b/process-wpt-results.js
index fb0edc7..1859b33 100644
--- a/process-wpt-results.js
+++ b/process-wpt-results.js
@@ -184,7 +184,9 @@ export function score_run (run, against_run, focus_areas_map) {
     for (const area of Object.keys(FOCUS_AREAS)) {
         scores[area] = {
             total_tests: 0,
-            total_score: 0
+            score_tests: 0,
+            total_subtests: 0,
+            score_subtests: 0,
         }
     }
 
@@ -203,29 +205,34 @@ export function score_run (run, against_run, focus_areas_map) {
         const subtest_names = Object.keys(subtests)
         if (!subtest_names.length) {
             for (const area of areas) {
-                scores[area].total_score += run_test.score
+                scores[area].score_tests += run_test.score
+                scores[area].total_subtests += 1
+                scores[area].score_subtests += run_test.score
             }
         } else {
-            let test_score = 0
+            let score = 0
             for (const subtest of subtest_names) {
                 if (Object.hasOwn(run_test.subtests, subtest)) {
-                    test_score += run_test.subtests[subtest].score
+                    score += run_test.subtests[subtest].score
                 }
             }
-            test_score /= subtest_names.length
             for (const area of areas) {
-                scores[area].total_score += test_score
+                scores[area].score_tests += score / subtest_names.length
+                scores[area].total_subtests += subtest_names.length
+                scores[area].score_subtests += score
             }
         }
     }
 
-    return Object.entries(scores).reduce((scores, [area, totals]) => {
-        scores[area] = 0
+    for (const [area, totals] of Object.entries(scores)) {
         if (totals.total_tests !== 0) {
-            scores[area] = Math.floor(
-                1000 * totals.total_score / totals.total_tests
+            scores[area].per_mille = Math.floor(
+                1000 * totals.score_tests / totals.total_tests
             )
+        } else {
+            scores[area].per_mille = 0
         }
-        return scores
-    }, {})
+    }
+
+    return scores
 }
diff --git a/site/load-chart.js b/site/load-chart.js
index 94c6a57..c8da9b6 100644
--- a/site/load-chart.js
+++ b/site/load-chart.js
@@ -1,7 +1,9 @@
 /* global google */
+/* global all_scores */
 
 google.charts.load('current', { packages: ['corechart', 'line'] })
 google.charts.setOnLoadCallback(setupChart)
+all_scores = null
 
 const fetchData = fetch('scores.json')
 const embed = location.search === '?embed'
@@ -107,7 +109,6 @@ function setupChart () {
     const period_dropdown = document.getElementById('selected-period')
     const show_legacy = document.getElementById('show-legacy')
     const chart = new google.visualization.LineChart(node)
-    let all_scores
 
     Object.keys(periodRanges).forEach(date => {
         const selector = document.createElement('option')
diff --git a/test/process-wpt-results.test.js b/test/process-wpt-results.test.js
index d3d699a..3dc2053 100644
--- a/test/process-wpt-results.test.js
+++ b/test/process-wpt-results.test.js
@@ -166,11 +166,23 @@ describe('Scoring', () => {
             test2: ['all']
         }
         let score = score_run(run, run, focus_area_map)
-        assert.deepEqual(score.all, 1000)
+        assert.deepEqual(score.all, {
+            per_mille: 1000,
+            score_subtests: 2,
+            score_tests: 2,
+            total_subtests: 2,
+            total_tests: 2,
+        })
 
         run.test_scores.test2.score = 0
         score = score_run(run, run, focus_area_map)
-        assert.deepEqual(score.all, 500)
+        assert.deepEqual(score.all, {
+            per_mille: 500,
+            score_subtests: 1,
+            score_tests: 1,
+            total_subtests: 2,
+            total_tests: 2,
+        })
     })
     it('calculates scores for subtests', () => {
         const run = {
@@ -187,7 +199,13 @@ describe('Scoring', () => {
         }
 
         const score = score_run(run, run, { test1: ['all'] })
-        assert.equal(score.all, 1000)
+        assert.deepEqual(score.all, {
+            per_mille: 1000,
+            score_subtests: 3,
+            score_tests: 1,
+            total_subtests: 3,
+            total_tests: 1,
+        })
     })
     it('calculates scores for subtests by averaging', () => {
         const run = {
@@ -204,7 +222,13 @@ describe('Scoring', () => {
         }
 
         const score = score_run(run, run, { test1: ['all'] })
-        assert.equal(score.all, 333)
+        assert.deepEqual(score.all, {
+            per_mille: 333,
+            score_subtests: 1,
+            score_tests: 0.3333333333333333,
+            total_subtests: 3,
+            total_tests: 1,
+        })
     })
     it('calculates scores correctly even subtest name collides with JS builtins', () => {
         const run = {
@@ -237,7 +261,13 @@ describe('Scoring', () => {
         }
 
         const score = score_run(run, against_run, { test1: ['all'], test2: ['all'] })
-        assert.equal(score.all, 500)
+        assert.deepEqual(score.all, {
+            per_mille: 500,
+            score_subtests: 1,
+            score_tests: 1,
+            total_subtests: 2,
+            total_tests: 2,
+        })
     })
     it('calculates scores based only on tests in new runs', () => {
         const old_run = {
@@ -258,11 +288,23 @@ describe('Scoring', () => {
             test1: all, test2: all, test3: all
         }
         let score = score_run(old_run, new_run, focus_map)
-        assert.equal(score.all, 0)
+        assert.deepEqual(score.all, {
+            per_mille: 0,
+            score_subtests: 0,
+            score_tests: 0,
+            total_subtests: 1,
+            total_tests: 2,
+        })
 
         old_run.test_scores.test3.score = 1
         score = score_run(old_run, new_run, focus_map)
-        assert.equal(score.all, 500)
+        assert.deepEqual(score.all, {
+            per_mille: 500,
+            score_subtests: 1,
+            score_tests: 1,
+            total_subtests: 1,
+            total_tests: 2,
+        })
     })
 })