[larsnystrom]

According to npmjs.com react has 13.6M downloads/week and redux has 6.7M. So 45-50% sounds about right.

[sroussey]

Tip: If you want to increase your numbers relative to another package, ship more versions over the same time period.

[ratww]

That figure is "Weekly Downloads", not in total. None of them had updates in less than two months. Also, React has published 10x more versions than Redux. So if anything, Redux might be more popular than GP assumed.