At Colgan on the Dash 8 in Newark, 20% of all the trips are day trips. Followed by 21% continuous duty overnights, 49% 4 days, 6% 3 days and 4% 2 day trips.
I flew day trips last week (I am a commuter and hate them). They were long days worth decent money. Show at 0930 or so and fly a round trip somewhere then sit for 3 hours which turns into 4+ and then do another turn, get delayed trying to get back and end around 2300 or so. Scheduled they would have been done at 2130 for a 12 hour day.