Critics and Twitter users pretty much hated Sunday’s Oscarcast, and now we know the rest of America did, too. According to Nielsen, the Franthaway-hosted event was seen by 37.6 million viewers, a roughly 10 percent decline from 2010’s audience of 41.3 million. And despite jokes about appealing to advertiser-friendly demos, the show was a bust on that count, too: Oscar 2011 notched an 11.7 rating with viewers under 50 — down 13 percent in the demo. (The show did a little better with adults 18 to 34, dipping a more modest 5 percent.) The declines end two years of ratings gains by the Oscars and come at a time when other major awards shows (including the Grammys and Golden Globes) have seen Nielsen upticks. ABC says it won’t have data on how the show’s numbers changed throughout the three-hour-plus broadcast until tomorrow. We’re willing to wager they didn’t go up during the course of the show.