Shares of tech giant, Alphabet (GOOGL  ) fell 2.5% after hours on Thursday to the $840 level after releasing mixed fourth quarter earnings. The parent to Google (GOOG  ) announced earnings per share of 9.36 with revenue at $26.06 billion. This was lower than the average expectation of all analysts covering the company. Analysts had expected earnings of $9.64 a share and $25.23 billion in revenue. It was reported that a one time tax adjustment was the reason for the miss on earnings per share. The company adjusted to a tax rate of 22% last quarter versus 16% in the third quarter.

The positive part of the report was revenue at $26.06 billion. This beat represents a 22% gain from this time last year which, according to the chief financial officer, came from YouTube and mobile search ad revenue. In the conference call the CEO said that "in 2016 mobile search surpassed desktop search", and it appears that Alphabet was able to benefit from it.

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On their advertising platform, cost per click declined 15% from the prior year. Compare that to 11% from the third quarter and Alphabet was left to explain how advertisers aren't willing to pay as much for mobile advertisements as they did for desktop.

"Other bets", which is Alphabets "startup" division showed revenue of $262 million which was up from $150 million last year. Though many names were able to show progress, it was noted that this portion of Alphabet has really yet to show any real, meaningful change in revenue.

"Other revenue" which includes the companies smart phone offering the "Pixel" and google home added $3.4 billion which was an increase of 62%. Interestingly the company didn't show sales of either product.

Though shares took a hit in after hours trading, investors were eager to buy that dip. Shares opened slightly higher by the morning session.