Table:
|  | Number of Options | Weighted average exercise price | Weighted average remaining contractual life (years) | Aggregate intrinsic value $ |
| --- | --- | --- | --- | --- |
| Outstanding, January 1, 2018 | 1,368,772 | $3.12 |  |  |
| Granted – 2018 | 401,099 | $9.27 |  |  |
| Exercised – 2018 | (165,169) | $3.16 |  |  |
| Expired – 2018 | (50,002) | $5.48 |  |  |
| Outstanding, December 31, 2018 | 1,554,700 | $4.63 | 3.0 |  |
| Granted – 2019 | 410,134 | $12.28 |  |  |
| Exercised – 2019 | (251,063) | $3.73 |  |  |
| Expired – 2019 | (89,550) | $12.55 |  |  |
| Outstanding, December 31, 2019 | 1,624,221 | $6.27 | 2.6 | $7,925,643 |
| Exercisable, December 31, 2019 | 1,143,637 | $4.39 | 1.9 | $7,197,053 |
Paragraphs:
NOTE 11 – STOCK COMPENSATION
The Company sponsors a stock-based incentive compensation plan known as the 2013 Equity Compensation Plan (the “Plan”), which was established by the Board of Directors of the Company in June 2013. A total of 500,000 shares were initially reserved for issuance under the Plan. The Plan was amended several times since then to eventually increase the authorized shares to 2,500,000 as of December 31, 2019. A total of 1,624,221 shares of common stock underlying options were outstanding at December 31, 2019. The Company had 236,614 remaining shares available to grant under the Plan at December 31, 2019.
The Plan allows the Company to grant incentive stock options, non-qualified stock options, stock appreciation rights, or restricted stock. The incentive stock options are exercisable for up to ten years, at an option price per share not less than the fair market value on the date the option is granted. The incentive stock options are limited to persons who are regular full-time employees of the Company at the date of the grant of the option. Non-qualified options may be granted to any person, including, but not limited to, employees, independent agents, consultants and attorneys, who the Company’s Board or Compensation Committee believes have contributed, or will contribute, to the success of the Company. Non-qualified options may be issued at option prices of less than fair market value on the date of grant and may be exercisable for up to ten years from date of grant. The option vesting schedule for options granted is determined by the Compensation Committee of the Board of Directors at the time of the grant. The Plan provides for accelerated vesting of unvested options if there is a change in control, as defined in the Plan.
The compensation cost that has been charged against income related to options for the years ended December 31, 2019 and 2018, was $1,687,745 and $1,317,904, respectively. No income tax benefit was recognized in the income statement and no compensation was capitalized in any of the years presented.
The Company had the following option activity during the years ended December 31, 2019 and 2018:
Of the options outstanding at December 31, 2019, 1,143,637 were exercisable with a weighted average contractual life of 1.9 years.
Question:
What is the percentage change in the number of shares outstanding at the end of 2018 compared to the start of 2018?
Answer: (1554700-1368772)/1368772  = 13.58