How to counter Warwick
Let us take a look on how to beat Warwick. We will look at champions who are strong against Warwick and who are weak against Warwick. Use win rate, gold difference and creep score difference at minute 10 to find the best 
Top champion who counters Warwick. You can already win in champion select with the right counters for Warwick. If you want to know how to counter Warwick then you need to take into account the best picks vs Warwick and the worst picks vs Warwick. This Warwick counter data is based on matches played by Pros on patch 14.21 and previous ones. It is important to see whether Pros counter picked Warwick or whether they played as Warwick.
Champions used by Pros to counter pick Warwick
Looking at the matches from Pros (see table Pros counter picked Warwick) we can see that they picked 
Gnar most often to counter pick Warwick. The matchup Gnar vs Warwick occured 15 times. Warwick has 8 wins and 7 losses in this matchup. Learn how to counter pick Gnar to get another perspective on the data.
Lane outcome for Warwick
When looking at Warwick counters you will notice that win rates alone are not conclusional. Therefore we provide an overview (see table Lane Outcome) where you can see the lane outcome of Pros who played Warwick. The lane outcome of Warwick consists of three outcomes: Win, Loss or Draw. Let's take a look of Warwick lane and match outcome for specific matchups. Considering the lane outcome and the match outcome of a specific matchup, might enable you to find the right counter for Warwick.
Conclusion
Analyze the available data and learn how to beat Warwick. To master Warwick take also a look on Warwick builds and runes for Warwick. Good luck, Summoner!