Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Week | Date | Opponent | Result | Attendance |
| --- | --- | --- | --- | --- |
| 1.0 | September 7, 1980 | Detroit Lions | L 41-20 | 64892.0 |
| 2.0 | September 11, 1980 | at Tampa Bay Buccaneers | L 10-9 | 66576.0 |
| 3.0 | September 21, 1980 | Green Bay Packers | W 51-21 | 63850.0 |
| 4.0 | September 28, 1980 | at New York Giants | W 28-7 | 73414.0 |
| 5.0 | October 5, 1980 | San Francisco 49ers | W 48-26 | 62188.0 |
| 6.0 | October 12, 1980 | at St. Louis Cardinals | W 21-13 | 50230.0 |
| 7.0 | October 19, 1980 | at San Francisco 49ers | W 31-17 | 55360.0 |
| 8.0 | October 26, 1980 | at Atlanta Falcons | L 13-10 | 57401.0 |
| 9.0 | November 2, 1980 | New Orleans Saints | W 45-31 | 59909.0 |
| 10.0 | November 9, 1980 | Miami Dolphins | L 35-14 | 62198.0 |
| 11.0 | November 16, 1980 | at New England Patriots | W 17-14 | 60609.0 |
| 12.0 | November 24, 1980 | at New Orleans Saints | W 27-7 | 53448.0 |
| 13.0 | November 30, 1980 | New York Jets | W 38-13 | 59743.0 |
| 14.0 | December 7, 1980 | at Buffalo Bills | L 10-7 (OT) | 77133.0 |
| 15.0 | December 15, 1980 | Dallas Cowboys | W 38-14 | 65154.0 |
| 16.0 | December 21, 1980 | Atlanta Falcons | W 20-17 (OT) | 62469.0 |
Question:
Which Attendance has a Result of w 51-21?
Answer:
63850.0