Alphabet has been talking nonstop about AI. Now investors are looking for proof that the company’s efforts are working.

Cloud revenue in the quarter of $12 billion—a 30% increase from last year—just misses analysts’ estimates of $12.2 billion.

As of 11:15 a.m. ET, the stock was down by 8.1%. Overall revenue rose 12% to $96.5 billion in Q4, slightly below analysts' consensus estimate of $96.67 billion. That revenue growth was balanced with search revenue up 12.5% to $54 billion, YouTube up 13.8% to $10.5 billion, and its third-party Google Network ad revenue continuing to decline.