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:
| District | Incumbent | Party | First elected | Result | Candidates |
| --- | --- | --- | --- | --- | --- |
| Pennsylvania 1 | Thomas Foglietta | Democratic | 1980.0 | Re-elected | Thomas Foglietta (D) 87.50% James Cella (R) 12.49% |
| Pennsylvania 2 | Chaka Fattah | Democratic | 1994.0 | Re-elected | Chaka Fattah (D) 87.99% Larry Murphy (R) 12.01% |
| Pennsylvania 4 | Ron Klink | Democratic | 1992.0 | Re-elected | Ron Klink (D) 64.20% Paul Adametz (R) 35.76% |
| Pennsylvania 5 | Bill Clinger | Republican | 1978.0 | Retired Republican hold | John E. Peterson (R) 60.26% Ruth Rudy (D) 39.70% |
| Pennsylvania 9 | Bud Shuster | Republican | 1972.0 | Re-elected | Bud Shuster (R) 73.70% Monte Kemmler (D) 26.27% |
| Pennsylvania 11 | Paul Kanjorski | Democratic | 1984.0 | Re-elected | Paul Kanjorski (D) 68.00% Stephen Urban (R) 31.99% |
| Pennsylvania 12 | John Murtha | Democratic | 1974.0 | Re-elected | John Murtha (D) 69.99% Bill Choby (R) 30.00% |
| Pennsylvania 17 | George Gekas | Republican | 1982.0 | Re-elected | George Gekas (R) 72.23% Paul Kettl (D) 27.76% |
| Pennsylvania 20 | Frank Mascara | Democratic | 1994.0 | Re-elected | Frank Mascara (D) 53.89% Mike McCormick (R) 46.10% |
Question:
What is the earliest year where the result of the election was a retired republican hold?
Answer:
1978.0