Insomnia and Laughter
| Number of times a child laughs each day, on average: | 400 |
| Number of times an adult laughs each day, on overage: | 15 |
| Number of Americans with stress-related insomnia: | 1 in 5 |
| Number on any given day who need more sleep; | 45 million |
| Percentage decrease in average sleep time, since 1900: | 20 |