Table 1.

School closure data by cause between the 2002–2003 and 2018–2019 academic years.

Cause of school closure	Total days closed	Average closure length (days)	Fall semester days closed	Spring semester days closed	Student-days missed
Wildfires	21,442 (62.7%)	3.28	20,861 (78.7%)	581 (7.6%)	13,491,539 (72.3%)
Natural hazard impacts	8370 (24.5%)	1.78	2718 (10.3%)	5652 (73.7%)	3,208,048 (17.2%)
Infrastructure	2292 (6.7%)	1.33	1435 (5.4%)	857 (11.2%)	872,549 (4.7%)
Student safety	1660 (4.9%)	1.14	1292 (4.9%)	368 (4.8%)	1,002,170 (5.4%)
Other	419 (1.2%)	1.62	203 (0.8%)	216 (2.8%)	79,454 (0.4%)
Total	34,183	2.44	26,509	7674	18,653,777