Reddit's stock dropped over 15% after the CEO mentioned that traffic had been affected by a Google algorithm change.The impact highlights the reliance of some users on external search engines to find information on Reddit.Despite a 39% user growth between 2023 and 2024, Reddit reported user growth below analyst expectations for the fourth quarter.While revenue for the quarter reached $428 million, with 92% from advertising, the algorithm change primarily affected logged-out users.