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:
| Institution | Location | Nickname | Founded | Type | Enrollment | Joined |
| --- | --- | --- | --- | --- | --- | --- |
| George Fox University | Newberg, Oregon | Bruins | 1885.0 | Private/Quaker | 3519.0 | 1996 |
| Lewis & Clark College | Portland, Oregon | Pioneers | 1867.0 | Private/Non-sectarian | 3433.0 | 1931, 1949 1 |
| Linfield College | McMinnville, Oregon | Wildcats | 1849.0 | Private/Baptist | 2664.0 | 1926 |
| Pacific University | Forest Grove, Oregon | Boxers | 1849.0 | Private/United Church of Christ | 3302.0 | 1926 |
| Pacific Lutheran University | Tacoma, Washington | Lutes | 1890.0 | Private/Lutheran | 3461.0 | 1965 |
| University of Puget Sound | Tacoma, Washington | Loggers | 1888.0 | Private/Non-sectarian | 2600.0 | 1926, 1996 2 |
| Whitman College | Walla Walla, Washington | Missionaries | 1859.0 | Private/Non-sectarian | 1475.0 | 1926 |
| Whitworth University | Spokane, Washington | Pirates | 1890.0 | Private/Presbyterian | 2886.0 | 1970, 1988 3 |
Question:
How many different items appear in the enrollment column that joined in 1931, 1949 1?
Answer:
1.0