I'm not sure where the parent is getting 15%; Google seems to be up ~23% YTD. Today's close was an all-time high, though that might get somewhat undone in the morning.

To your point, that seems to be a bit worse than tech (~26% YTD) but better than the S&P (17% YTD).

You need to also include the 7% after market drop which Google shares saw after declaring the results.