diff --git a/web/components/portfolio/portfolio-value-section.tsx b/web/components/portfolio/portfolio-value-section.tsx
index 706630b2..ab4bef0c 100644
--- a/web/components/portfolio/portfolio-value-section.tsx
+++ b/web/components/portfolio/portfolio-value-section.tsx
@@ -1,43 +1,26 @@
-import { PortfolioMetrics } from 'common/user'
 import { formatMoney } from 'common/util/format'
 import { last } from 'lodash'
-import { memo, useEffect, useState } from 'react'
-import { Period, getPortfolioHistory } from 'web/lib/firebase/users'
+import { memo, useRef, useState } from 'react'
+import { usePortfolioHistory } from 'web/hooks/use-portfolio-history'
+import { Period } from 'web/lib/firebase/users'
 import { Col } from '../layout/col'
 import { Row } from '../layout/row'
 import { PortfolioValueGraph } from './portfolio-value-graph'
-import { DAY_MS } from 'common/util/time'
-
-const periodToCutoff = (now: number, period: Period) => {
-  switch (period) {
-    case 'daily':
-      return now - 1 * DAY_MS
-    case 'weekly':
-      return now - 7 * DAY_MS
-    case 'monthly':
-      return now - 30 * DAY_MS
-    case 'allTime':
-    default:
-      return new Date(0)
-  }
-}
 
 export const PortfolioValueSection = memo(
   function PortfolioValueSection(props: { userId: string }) {
     const { userId } = props
 
     const [portfolioPeriod, setPortfolioPeriod] = useState<Period>('weekly')
-    const [portfolioHistory, setUsersPortfolioHistory] = useState<
-      PortfolioMetrics[]
-    >([])
+    const portfolioHistory = usePortfolioHistory(userId, portfolioPeriod)
 
-    useEffect(() => {
-      const cutoff = periodToCutoff(Date.now(), portfolioPeriod).valueOf()
-      getPortfolioHistory(userId, cutoff).then(setUsersPortfolioHistory)
-    }, [portfolioPeriod, userId])
+    // Remember the last defined portfolio history.
+    const portfolioRef = useRef(portfolioHistory)
+    if (portfolioHistory) portfolioRef.current = portfolioHistory
+    const currPortfolioHistory = portfolioRef.current
 
-    const lastPortfolioMetrics = last(portfolioHistory)
-    if (portfolioHistory.length === 0 || !lastPortfolioMetrics) {
+    const lastPortfolioMetrics = last(currPortfolioHistory)
+    if (!currPortfolioHistory || !lastPortfolioMetrics) {
       return <></>
     }
 
@@ -64,7 +47,7 @@ export const PortfolioValueSection = memo(
           </select>
         </Row>
         <PortfolioValueGraph
-          portfolioHistory={portfolioHistory}
+          portfolioHistory={currPortfolioHistory}
           includeTime={portfolioPeriod == 'daily'}
         />
       </>
diff --git a/web/hooks/use-portfolio-history.ts b/web/hooks/use-portfolio-history.ts
new file mode 100644
index 00000000..d5919783
--- /dev/null
+++ b/web/hooks/use-portfolio-history.ts
@@ -0,0 +1,32 @@
+import { useFirestoreQueryData } from '@react-query-firebase/firestore'
+import { DAY_MS, HOUR_MS } from 'common/util/time'
+import { getPortfolioHistoryQuery, Period } from 'web/lib/firebase/users'
+
+export const usePortfolioHistory = (userId: string, period: Period) => {
+  const nowRounded = Math.round(Date.now() / HOUR_MS) * HOUR_MS
+  const cutoff = periodToCutoff(nowRounded, period).valueOf()
+
+  const result = useFirestoreQueryData(
+    ['portfolio-history', userId, cutoff],
+    getPortfolioHistoryQuery(userId, cutoff),
+    { subscribe: true, includeMetadataChanges: true },
+    // Temporary workaround for react-query bug:
+    // https://github.com/invertase/react-query-firebase/issues/25
+    { refetchOnMount: 'always' }
+  )
+  return result.data
+}
+
+const periodToCutoff = (now: number, period: Period) => {
+  switch (period) {
+    case 'daily':
+      return now - 1 * DAY_MS
+    case 'weekly':
+      return now - 7 * DAY_MS
+    case 'monthly':
+      return now - 30 * DAY_MS
+    case 'allTime':
+    default:
+      return new Date(0)
+  }
+}
diff --git a/web/lib/firebase/users.ts b/web/lib/firebase/users.ts
index bad13c8c..c0764f0a 100644
--- a/web/lib/firebase/users.ts
+++ b/web/lib/firebase/users.ts
@@ -12,6 +12,7 @@ import {
   deleteDoc,
   collectionGroup,
   onSnapshot,
+  Query,
 } from 'firebase/firestore'
 import { getAuth } from 'firebase/auth'
 import { GoogleAuthProvider, signInWithPopup } from 'firebase/auth'
@@ -252,15 +253,13 @@ export async function unfollow(userId: string, unfollowedUserId: string) {
   await deleteDoc(followDoc)
 }
 
-export async function getPortfolioHistory(userId: string, since: number) {
-  return getValues<PortfolioMetrics>(
-    query(
-      collectionGroup(db, 'portfolioHistory'),
-      where('userId', '==', userId),
-      where('timestamp', '>=', since),
-      orderBy('timestamp', 'asc')
-    )
-  )
+export function getPortfolioHistoryQuery(userId: string, since: number) {
+  return query(
+    collectionGroup(db, 'portfolioHistory'),
+    where('userId', '==', userId),
+    where('timestamp', '>=', since),
+    orderBy('timestamp', 'asc')
+  ) as Query<PortfolioMetrics>
 }
 
 export function listenForFollows(