Netflix stock on Thursday rose about 8%, boosted by an announcement from hedge fund Pershing Square Capital Management LP that it had become a top 20 investor. The streamer’s stock, which closed at $386.70 a share on the Nasdaq, had been in decline after its earnings results last week revealed it had missed internal projections for new subscribers in the fourth quarter and experienced an expected slowdown in subscriber growth in the first quarter. Netflix subscriptions surged as the COVID-19 pandemic hit, but growth is slowing as businesses reopen and competition from streaming rivals rises.