Nails grow at an average rate of 0.1mm a day (1 cm every 100 days) Fingernails require 4 to 6 months to regrow completely. Toenails require 12 to 18 months. Actual growth rate is dependent upon age, season, exercise level, and hereditary factors.

So how long do you think these people have grown their nails. How many bottles of nail polish do they consume every week?