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Video: Compound Annual Growth Rate (CAGR) Definition
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 |
| Date |
Open |
High |
Low |
Close |
Volume |
| 04/13/2026 |
$0.58 |
$0.58 |
$0.55 |
$0.55 |
5.50K | | 04/14/2026 |
$0.55 |
$0.56 |
$0.55 |
$0.56 |
1.50K | | 04/15/2026 |
$0.56 |
$0.57 |
$0.53 |
$0.53 |
4.70K | | 04/16/2026 |
$0.54 |
$0.56 |
$0.54 |
$0.56 |
1.70K | | 04/17/2026 |
$0.56 |
$0.57 |
$0.54 |
$0.57 |
2.40K |
 |
| Protagenic Therapeutic is a development stage biopharmaceutical company focusing on the discovery and development of therapeutics to treat stress-related neuropsychiatric and mood disorders. Co.'s proprietary compound, PT00114, is a synthetic form of Teneurin Carboxy-terminal Associated Peptide (TCAP), an endogenous brain signaling peptide that can dampen overactive stress responses. Additionally, Co. is engaged in the research and development of follow-on compounds in the TCAP family. Co. is performing clinical trials to obtain Food and Drug Administration approval and commercialization of its product. | |
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PTIX (PTIX) has the following price history information. Looking back at PTIX historical stock prices for the last five trading days, on April 13, 2026, PTIX opened at $0.58, traded as high as $0.58 and as low as $0.55, and closed at $0.55. Trading volume was a total of 5.50K shares. On April 14, 2026, PTIX opened at $0.55, traded as high as $0.56 and as low as $0.55, and closed at $0.56. Trading volume was a total of 1.50K shares. On April 15, 2026, PTIX opened at $0.56, traded as high as $0.57 and as low as $0.53, and closed at $0.53. Trading volume was a total of 4.70K shares. On April 16, 2026, PTIX opened at $0.54, traded as high as $0.56 and as low as $0.54, and closed at $0.56. Trading volume was a total of 1.70K shares. On April 17, 2026, PTIX opened at $0.56, traded as high as $0.57 and as low as $0.54, and closed at $0.57. Trading volume was a total of 2.40K shares.
PTIX Historical Stock Prices By Date:

Below, we examine the compound annual growth rate — CAGR for short — of an investment into PTIX shares, starting with a $10,000 purchase of PTIX, and working forward through the historical stock price information to today.
Growth of $10,000.00
Without Dividends Reinvested
|
| Start date: |
04/28/2021 |
|
| End date: |
04/17/2026 |
|
| Start price/share: |
$125.44 |
|
| End price/share: |
$0.57 |
|
| Dividends collected/share: |
$0.00 |
|
| Total return: |
-99.55% |
|
| Average Annual Total Return: |
-66.20% |
|
| Starting investment: |
$10,000.00 |
|
| Ending investment: |
$45.45 |
|
| Years: |
4.97 |
|
|
 |
| Date |
Close |
| 04/13/2026 | $0.55 | | 04/14/2026 | $0.56 | | 04/15/2026 | $0.53 | | 04/16/2026 | $0.56 | | 04/17/2026 | $0.57 |
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