Number of registered voters in Multnomah County: 459,349
| Date | Ballots Received | Cumulative | Turnout Percentage |
| 4/07-4/27/2016 | 493 | 493 | 0.11% |
| 4/28/2016 | 376 | 869 | 0.19% |
| 4/29/2016 | 2,576 | 3,445 | 0.75% |
| 5/02/2016 | 13,434 | 16,879 | 3.67% |
| 5/03/2016 | 14,938 | 31,817 | 6.93% |
| 5/04/2016) | 7,108 | 38,925 | 8.47% |
| 5/05/2016 | 6,576 | 45,501 | 9.91% |
| 5/06/2016 | 8,640 | 54,141 | 11.79% |
| 5/09/2016 | 15,215 | 69,356 | 15.10% |
| 5/10/2016 | 10,073 | 79,429 | 17.29% |
| 5/11/2016 | 13,086 | 92,515 | 20.14% |
| 5/12/2016 | 8,721 | 101,236 | 22.04% |
| 5/13/2016 | 17,569 | 118,805 | 25.86% |
| 5/14/2016 | 4,979 | 123,784 | 26.95% |
| 5/16/2016 | 40,884 | 164,668 | 35.85% |
| 5/17/2016 | 94,347 | 259,015 | 56.39% |
Historical turnout: