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:
| Name | Position | Birth Date/Age at start of campaign | Games in campaign | Club |
| --- | --- | --- | --- | --- |
| Erich Burgener | GK | February 15, 1951 (age 31) | 3 | Servette |
| Roger Berbig | GK | November 6, 1954 (age 27) | 3 | Grasshoppers |
| Charly In-Albon | DF | June 23, 1957 (age 25) | 4 | Grasshoppers |
| Heinz Lüdi | DF | October 8, 1958 (age 23) | 4 | FC Zürich |
| Beat Rietmann | DF | October 24, 1961 (age 20) | 2 | FC St. Gallen |
| Andy Egli | DF | May 8, 1958 (age 24) | 6 | Grasshoppers |
| Alain Geiger | DF | November 5, 1960 (age 21) | 4 | Servette |
| Marco Schällibaum | DF | April 6, 1962 (age 20) | 1 | Grasshoppers |
| Marcel Koller | DF | November 11, 1960 (age 21) | 2 (both as sub) | Grasshoppers |
| René Botteron | MF | October 17, 1954 (age 27) | 1 | 1. FC Nuremberg\n FC Basel |
| Heinz Hermann | MF | March 28, 1958 (age 24) | 6 | Grasshoppers |
| Roger Wehrli | MF | March 18, 1956 (age 26) | 6 | Grasshoppers |
| Lucien Favre | MF | November 2, 1957 (age 24) | 5 (1 as sub) | Toulouse\n Servette |
| Alfred Scheiwiler | MF | February 4, 1956 (age 26) | 1 | Lausanne |
| Erni Maissen | MF | January 1, 1958 (age 24) | 1 (as sub) | FC Zürich\n FC Basel |
| Michel Decastel | MF | October 22, 1955 (age 26) | 3 | Servette |
| Ruedi Elsener | MF | February 18, 1953 (age 29) | 4 |  |
| Umberto Barberis | MF | June 5, 1952 (age 30) | 3 (1 as sub) | AS Monaco\n Servette |
| Andre Ladner | MF | May 20, 1962 (age 20) | 1 | Grasshoppers |
| Jean-Paul Brigger | ST | December 14, 1957 (age 24) | 2 (1 as sub) | Servette |
| Hans-Peter Zwicker | ST | April 7, 1960 (age 22) | 2 (both as sub) | FC Zürich\n Lausanne |
| Claudio Sulser | ST | October 8, 1955 (age 26) | 5 | Grasshoppers |
| Beat Sutter | ST | December 12, 1962 (age 19) | 2 (1 as sub) | FC Basel |
| Raimondo Ponte | ST | April 4, 1955 (age 27) | 4 | Grasshoppers |
| Manfred Braschler | ST | October 8, 1958 (age 23) | 2 | FC St. Gallen |
Question:
what was the average age of the grasshoppers?
Answer:
24