| Explanation of Responses: |
| (1) | The sale was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 7, 2020. |
| (2) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $177.1350 to $177.73. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (3) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $173.12 to $174.11. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (4) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $176.13 to $177.10. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (5) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $174.12 to $175.10. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (6) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $175.12 to $176.10. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (7) | Excluded from this Form 4 are 20,000 Class A common shares and 387,000 Class C capital shares previously reported as indirectly held through The Barton Foundation, a 501(c)(3) charitable foundation. Since the shares are held by a 501(c)(3) charitable foundation, the reporting person has no pecuniary interest in them. The reporting person previously reported the gifts of the shares to The Barton Foundation on Form 4s filed on August 27, 2014, November 7, 2016, November 14, 2017 and September 3, 2020. |
| (8) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $170.00 to $170.13. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (9) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $163.9050 to $164.86. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (10) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $168.99 to $169.86. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (11) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $164.99 to $165.98. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (12) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $167.99 to $168.97. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (13) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $166.99 to $167.9899. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (14) | The reported price is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $165.99 to $166.98. The reporting person will provide to the issuer, any security holder of the issuer, or the SEC staff, upon request, full information regarding the number of shares sold at each separate price within the range. |
| (15) | Date at which first vesting occurs is indicated. 1/4th of the total number of shares originally subject to the option become exercisable at the first vesting date and an additional 1/48th become exercisable each month thereafter until the option is fully vested. |