Table:
|  | 2018 | 2019 |
| --- | --- | --- |
| As per January 1: |  |  |
| Issued shares | 62,297,394 | 56,297,394 |
| Treasury shares | 6,157,241 | 6,978,496 |
| Outstanding shares | 56,140,153 | 49,318,898 |
| Changes during the year: |  |  |
| Cancellation of treasury shares | 6,000,000 | 5,000,000 |
| Share buybacks | 7,242,734 | 950,902 |
| Treasury shares used for share based performance programs | 421,479 | 498,224 |
| As per December 31: |  |  |
| Issued shares | 56,297,394 | 51,297,394 |
| Treasury shares | 6,978,496 | 2,431,174 |
| Outstanding shares | 49,318,898 | 48,866,220 |
Paragraphs:
TREASURY SHARES
On December 31, 2019, we had 48,866,220 outstanding common shares excluding 2,431,174 treasury shares. This compared to 49,318,898 outstanding common shares and 6,978,496 treasury shares at year-end 2018. Besides the cancellation of 5 million treasury shares in July 2019, the change in the number of treasury shares in 2019 was the result of approximately 950,000 repurchased shares and approximately 498,000 treasury shares that were used as part of share based payments.
Question:
What is the percentage change in  Share buybacks from during the year 2018 to during the year 2019?
Answer:  (950902-7242734)/ 7242734 = -86.87