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:
| Date | Opponent | Score | Loss | Attendance | Record |
| --- | --- | --- | --- | --- | --- |
| April 8 | Phillies | 7 - 6 11 | Lersch (0-1) | 40796.0 | 1-0 |
| April 9 | Phillies | 11 - 3 | Wise (0-1) | 6297.0 | 2-0 |
| April 10 | Phillies | 6 - 2 | Fryman (0-1) | 5422.0 | 3-0 |
| April 11 | Expos | 1 - 0 12 | Sembera (0-1) | 7281.0 | 4-0 |
| April 12 | Expos | 7 - 3 | Jenkins (0-1) | 28599.0 | 4-1 |
| April 13 | Expos | 7 - 6 | Stoneman (0-2) | 27664.0 | 5-1 |
| April 14 | Pirates | 4 - 0 | Veale (1-1) | 3114.0 | 6-1 |
| April 15 | Pirates | 7 - 4 | Ellis (1-1) | 4362.0 | 7-1 |
| April 16 | @ Cardinals | 1 - 0 | Carlton (1-1) | 16418.0 | 8-1 |
| April 17 | @ Cardinals | 3 - 0 | Giusti (1-1) | 11350.0 | 9-1 |
| April 19 | @ Expos | 6 - 5 11 | Shaw (1-2) | 16005.0 | 10-1 |
| April 20 | @ Expos | 6 - 3 | Morton (0-1) | 0.0 | 11-1 |
| April 20 | @ Expos | 4 - 2 | J. Niekro (0-1) | 28025.0 | 11-2 |
| April 22 | @ Pirates | 7 - 5 | Hands (2-1) | 0.0 | 11-3 |
| April 22 | @ Pirates | 6 - 5 | Nye (0-1) | 7906.0 | 11-4 |
| April 24 | Cardinals | 3 - 2 | Holtzman (2-1) | 11656.0 | 11-5 |
| April 25 | @ Mets | 3 - 1 | Seaver (1-2) | 18548.0 | 12-5 |
| April 26 | @ Mets | 9 - 3 | Cardwell (0-3) | 16252.0 | 13-5 |
| April 27 | @ Mets | 8 - 6 | Koonce (0-2) | 0.0 | 14-5 |
| April 27 | @ Mets | 3 - 0 | Nye (0-2) | 37437.0 | 14-6 |
| April 28 | @ Phillies | 2 - 1 10 | Wise (2-2) | 4438.0 | 15-6 |
| April 29 | @ Phillies | 10 - 0 | Jackson (2-2) | 3811.0 | 16-6 |
| April 30 | @ Phillies | 3 - 1 | Hands (3-2) | 2930.0 | 16-7 |
Question:
What is the average attendance that has april 12 as the date?
Answer:
28599.0