Amphastar Pharmaceuticals, Inc. (AMPH) NASDAQ

Currency In USD

AMPH Historical Return

If you invested $1000 in Amphastar Pharmaceuticals, Inc. (AMPH) 10 years ago, it would be worth $1,079.46 as of August 22, 2026, based on a reinvested dividends scenario. Over the same period, a $1000 investment made 5 years ago would be worth $1,126.76, while $1000 invested 1 year ago would be worth $708.2. This corresponds to total returns of 7.95%, 12.68%, -29.18%, respectively, with annualized returns of 0.77%, 2.42%, -29.18%.

Custom investment amounts or purchase dates can also be explored using the Stoculator calculator. Past performance does not guarantee future results.

AMPH Historical Data

Date Range:

Date	Open	Close	Adj Close	High	Low	Volume
August 21, 2026	21.64	21.6	21.6	22.2	21.44	376,557
August 20, 2026	21.38	21.68	21.68	21.76	21.24	338,696
August 19, 2026	21.64	21.74	21.74	21.99	21.15	410,770
August 18, 2026	21.11	21.34	21.34	21.59	21.08	411,802
August 17, 2026	20.9	20.86	20.86	21.23	20.77	533,504
August 14, 2026	20.02	20.91	20.91	21.07	19.89	305,681
August 13, 2026	20.18	20.18	20.18	20.27	19.84	307,442
August 12, 2026	20.16	19.98	19.98	20.22	19.61	341,042
August 11, 2026	20.02	20.42	20.42	20.57	20	0
August 10, 2026	20.74	20.31	20.31	20.9	19.55	645,738
August 07, 2026	22.48	20.78	20.78	22.65	20.4	1.3M
August 06, 2026	20.22	19.81	19.81	20.25	19.6	526,645
August 05, 2026	20.06	20.24	20.24	20.28	19.88	351,618
August 04, 2026	20.11	19.9	19.9	20.38	19.86	481,647
August 03, 2026	20.11	20.22	20.22	20.45	19.7	413,179
July 31, 2026	20.35	19.94	19.94	20.41	19.67	367,623
July 30, 2026	20.31	20.38	20.38	20.53	19.95	355,683
July 29, 2026	20.24	20.58	20.58	20.7	19.99	321,672
July 28, 2026	19.38	20.15	20.15	20.27	19.38	390,836
July 27, 2026	18.97	19.18	19.18	19.31	18.96	285,917
July 24, 2026	18.9	18.72	18.72	19.12	18.5	445,682
July 23, 2026	19.08	18.87	18.87	19.34	18.73	650,429
July 22, 2026	19.71	19.3	19.3	19.95	19.2	409,242
July 21, 2026	19.42	19.59	19.59	19.89	19.42	620,355
July 20, 2026	19.78	19.63	19.63	19.91	19.52	437,415
July 17, 2026	19.84	19.75	19.75	20.35	19.63	338,456
July 16, 2026	19.4	19.86	19.86	20.14	19.4	416,837
July 15, 2026	18.87	19.4	19.4	19.5	18.83	356,066
July 14, 2026	19.1	18.81	18.81	19.39	18.41	334,746
July 13, 2026	19	19.29	19.29	19.68	18.95	384,429
July 10, 2026	18.97	18.72	18.72	19.15	18.61	311,051
July 09, 2026	18.86	19.02	19.02	19.13	18.61	446,628
July 08, 2026	19.96	18.88	18.88	19.96	18.52	438,664
July 07, 2026	20.06	20.08	20.08	20.28	19.74	449,983
July 06, 2026	19.48	19.61	19.61	20.01	19.08	313,781
July 02, 2026	20.35	19.64	19.64	20.35	19.63	315,753
July 01, 2026	20.32	20.1	20.1	20.54	19.91	422,109
June 30, 2026	20.71	20.18	20.18	20.71	19.86	400,207
June 29, 2026	21.12	20.71	20.71	21.24	19.66	727,053
June 26, 2026	21.01	21.78	21.78	21.81	20.88	623,977
June 25, 2026	21	21.04	21.04	22	20.79	481,265
June 24, 2026	19.77	21.02	21.02	21.09	19.77	701,032
June 23, 2026	18.61	19.53	19.53	19.58	18.5	660,867
June 22, 2026	18.8	18.33	18.33	18.9	18.22	767,365
June 18, 2026	19.51	18.81	18.81	19.66	18.7	1.33M
June 17, 2026	19.94	19.41	19.41	20.26	19.15	1.01M
June 16, 2026	19.91	19.96	19.96	20.41	19.61	724,186
June 15, 2026	20.11	19.71	19.71	20.29	19.59	586,137
June 12, 2026	19.9	20.09	20.09	20.55	19.9	377,788
June 11, 2026	20.15	20.53	20.53	20.65	20.1	463,541
June 10, 2026	20.21	20.29	20.29	20.77	19.99	405,165
June 09, 2026	19.53	20.16	20.16	20.27	19.53	506,256
June 08, 2026	19.75	19.39	19.39	19.85	19.34	558,989
June 05, 2026	18.86	19.74	19.74	20.14	18.85	748,242
June 04, 2026	18.28	18.7	18.7	18.9	18.28	459,231
June 03, 2026	18.26	18.12	18.12	18.36	17.73	492,109
June 02, 2026	18.36	18.45	18.45	18.67	18.1	810,460
June 01, 2026	18.63	18.42	18.42	19.01	18.22	569,685
May 29, 2026	19.28	18.85	18.85	19.46	18.55	848,896
May 28, 2026	19.04	19.3	19.3	19.55	19.02	621,213