Table 3. Cumulative probability of seroconverting over time.

Date	At risk		Events		Censored		Probability (95% CI)
	Non-HCW	HCW	Non-HCW	HCW	Non-HCW	HCW	Non-HCW	HCW
4/16/2020	154	46	0	0	0	0	0.00 (0.00,0.00)	0.00 (0.00,0.00)
5/16/2020	509	1172	19	31	20	37	0.08 (0.04,0.12)	0.07 (0.03,0.12)
6/15/2020	1777	1411	115	61	266	63	0.17 (0.14,0.21)	0.11 (0.07,0.16)
7/15/2020	1969	2267	162	170	960	274	0.24 (0.21,0.28)	0.19 (0.14,0.23)
8/14/2020	2421	2569	89	54	207	105	0.27 (0.24,0.31)	0.2 (0.16,0.24)
9/13/2020	2303	2548	22	34	211	94	0.28 (0.24,0.31)	0.22 (0.17,0.25)
10/13/2020	1635	2312	40	22	630	236	0.29 (0.26,0.33)	0.22 (0.18,0.26)
11/12/2020	2481	2467	66	69	363	397	0.32 (0.28,0.35)	0.24 (0.2,0.28)
12/12/2020	3122	2580	69	52	247	210	0.34 (0.3,0.37)	0.26 (0.22,0.3)
1/11/2021	4318	2802	212	339	722	365	0.37 (0.34,0.4)	0.34 (0.3,0.38)
2/10/2021	3450	996	612	2023	3007	618	0.45 (0.42,0.48)	0.77 (0.75,0.79)

HCW = healthcare worker.