Alphabet missed Wall Street’s estimates, reporting operating income of $7.66 billion in its fourth quarter, sending shares down sharply in after-hours trading.

The parent company of Google reported a 24% revenue gain in the period ending December 31 of $32.3 billion, topping analyst projections of $31.85 billion. But Alphabet said it earned $9.70 per share, well below consensus estimates of $9.96.

The $9.70 excludes the impact of the Tax Act, which was enacted on December 22. The new law saddled Alphabet with $9.9 billion in the quarter, primarily due to the one-time transition tax on accumulated foreign subsidiary earnings and deferred tax impacts.

Alphabet

When the tax impact is included, as suggested by generally accepted accounting principles, the company actually swung to a loss of $4.35 a share, or $3.02 billion.

Along with the quarterly numbers, the company said its board would be chaired by John L. Hennessy, who has been a board member since 2004. He replaces Eric Schmidt, who resigned as executive board chairman in December in the wake of an article detailing workplace relationships and blurred boundaries between managers and subordinates at Google.

Google continues to dominate the digital ad market, raking in $83.4 billion in worldwide revenue — or about one-third share of the global market, according to eMarketer. Facebook ranks second with an 18% share.

YouTube contributes about 11% of Google’s total ad revenue, eMarketer estimates. Its ad revenue is forecast to reach $9.13 billion for 2017.

Alphabet executives are speaking to Wall Street analysts during a conference call shortly. Check back for updates.