Transaction Details

Footnotes

The price reported in Column 4 is a weighted-average price. The shares were sold in multiple transactions at prices ranging from $37.30 to $38.5596 inclusive. The reporting person undertakes to provide to NGS, any security holder of NGS, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. | The price reported in Column 4 is a weighted-average price. The shares were sold in multiple transactions at prices ranging from $37.1538 to $37.3455 inclusive. The reporting person undertakes to provide to NGS, any security holder of NGS, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. | Not applicable. Each Restricted Stock Unit represents the right to receive one share of the Issuer's common stock upon vesting.