ESPN ran a graphic about the Celtics FG% in crunch time at various time intervals. They excluded OT data and were using FG% instead of EFG%, so I thought I'd run the numbers and compare to Denver including OT and using EFG%. I chose Denver because they are the team universally regarded as the best crunch time offense. These numbers are inclusive (meaning 5 minute number include all the 4 minutes and less numbers, and so on):
With the score within -5 to +5, time left in 4th quarter and/or OT.
10 seconds left: Boston 12.5% (1-6 2s, 0-2 3s), Denver 62.5% (1-2, 1-2)
30 seconds left: Boston 19.0% (4-14, 0-7), Denver 40.0% (3-7, 2-8)
1 minute left: Boston 51.2% (11-24, 7-18), Denver 45.7% (10-17, 4-18)
2 minutes left: Boston 51.7% (24-49, 15-41), Denver 61.4% (35-50, 9-29)
3 minutes left: Boston 52.3% (37-73, 21-58), Denver 71.3% (51-78, 14-43)
4 minutes left: Boston 53.1% (45-88, 27-73), Denver 64.0% (67-101, 21-53)
5 minutes left: Boston 53.6% (58-109, 31-86), Denver 62.9% (82-122, 25-68)
Edit: Fixed an error 16.7%->12.5% for Boston EFG% with 10 seconds or less.