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:
| Outcome | Year | Championship | Surface | Partner | Opponents | Score |
| --- | --- | --- | --- | --- | --- | --- |
| Runner-up | 1915.0 | U.S. Championships | Grass | Irving Wright | Harry Johnson Hazel Hotchkiss Wightman | 0–6, 1–6 |
| Winner | 1917.0 | U.S. Championships | Grass | Irving Wright | Bill Tilden Florence Ballin | 10–12, 6–1, 6–3 |
| Runner-up | 1918.0 | U.S. Championships | Grass | Fred Alexander | Irving Wright Hazel Hotchkiss Wightman | 2–6, 3–6 |
| Runner-up | 1920.0 | U.S. Championships | Grass | Craig Biddle | Wallace Johnson Hazel Hotchkiss Wightman | 4–6, 3–6 |
| Runner-up | 1921.0 | U.S. Championships | Grass | Bill Tilden | Bill Johnston Mary Browne | 6–3, 4–6, 3–6 |
| Winner | 1922.0 | U.S. Championships (2) | Grass | Bill Tilden | Howard Kinsey Helen Wills Moody | 6–4, 6–3 |
| Winner | 1923.0 | U.S. Championships (3) | Grass | Bill Tilden | John Hawkes Kitty McKane Godfree | 6–3, 2–6, 10–8 |
Question:
What is the earliest year?
Answer:
1915.0