If your subscriber count has decreased more than usual around December 13-14, it could be due to the recent removal of spam subscriptions. If that’s the case, you’ll see an alert in YouTube Studio letting you know. Here’s more info: https://goo.gl/5GEAuS
@YouTube @TeamYouTube I had 80 subscribers, but a few days ago. Maybe yesterday I don’t remember. My subscribers decreased to 53! I read the article and supposedly “spam accounts” were subscribing to me and now you are removing them! Please help! I earned those subscribers! 

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