Best way to have a snapshot-based QuickSight histogram

I have a cron job that exports a list of number of messages per user frequencies such as:

• 10 * 1
• 5 * 2
• 8 * 3

(Which means: 8 users have posted 3 messages)

I'd like to have a histogram chart which displays last snapshot's data (ie. bar, mean, avg).

I was thinking of TimeStream, but it actually accumulate. What is the recommended storage for this usecase?