Table 2.

Data set of USA (Pham 2020)

Date	Count	Date	Count	Date	Count	Date	Count	Date	Count
Feb 29	1	March 1	1	2	6	3	9	4	11
5	12	6	15	7	19	8	22	9	26
10	30	11	38	12	41	13	48	14	58
15	73	16	95	17	121	18	171	19	239
20	309	21	374	22	509	23	689	24	957
25	1260	26	1614	27	2110	28	2754	29	3251
30	3948	31	5027	April 1	6263	2	7438	3	8694
4	10,231	5	11,632	6	13,128	7	15,347	8	17,503
9	19,604	10	21,830	11	23,843	12	25,558	13	27,272
14	29,825	15	32,443	16	34,619	17	37,147	18	39,014
19	40,575	20	42,514	21	45,179	22	47,520