| Table 1. U.S. Natural Gas Reserves and Reserve Changes for FRS Companies, 1986-1999 | |
| (Trillion cubic feet) | |
| Beginning Reserves, 1986 | 83.7 |
| Reserve Additions, 1986-1999 | 95.6 |
| Purchases, 1986-1999 | 25.3 |
| Production, 1986-1999 | -109 |
| Sales, 1986-1999 | -31.2 |
| Entry & Exit, net | 6.6 |
| Ending Reserves, 1999 | 70.9 |
| Source: Energy Information Administration, Form EIA-28 (Financial Reporting System) | |