Online travel stocks are underperforming on a day when Expedia (EXPE -2.2%) announced it's buying 61% of popular German hotel bookings site Trivago. PCLN -2.4%. TRIP -2.7%. OWW -4.6%. TZOO -3.3%. Priceline received 83% of its Q3 gross bookings from international markets, and the bulk of that came from Europe.