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:
| City | Population | Registered voters | Democratic | Republican | D–R spread | Other | No party preference |
| --- | --- | --- | --- | --- | --- | --- | --- |
| Carlsbad | 102342.0 | 64.7% | 28.0% | 42.0% | -14.0% | 8.5% | 24.9% |
| Chula Vista | 236218.0 | 48.2% | 42.0% | 27.7% | +14.3% | 6.9% | 26.1% |
| Coronado | 19423.0 | 55.0% | 24.5% | 47.3% | -22.8% | 8.0% | 23.5% |
| Del Mar | 4175.0 | 77.2% | 34.2% | 34.7% | -0.5% | 7.4% | 26.7% |
| El Cajon | 98813.0 | 40.9% | 33.7% | 37.4% | -3.7% | 9.5% | 23.2% |
| Encinitas | 59223.0 | 67.8% | 35.1% | 32.8% | +2.3% | 9.0% | 26.4% |
| Escondido | 142573.0 | 41.8% | 28.3% | 42.4% | -14.1% | 9.3% | 23.7% |
| Imperial Beach | 26348.0 | 42.9% | 37.1% | 26.7% | +10.4% | 10.4% | 29.6% |
| La Mesa | 56722.0 | 58.3% | 37.9% | 32.5% | +5.4% | 9.8% | 23.6% |
| Lemon Grove | 25250.0 | 51.2% | 44.5% | 27.7% | +16.8% | 8.4% | 22.6% |
| National City | 58015.0 | 32.9% | 48.9% | 19.5% | +29.4% | 7.0% | 27.2% |
| Oceanside | 166139.0 | 50.5% | 31.6% | 37.8% | -6.2% | 9.2% | 25.1% |
| Poway | 47762.0 | 61.5% | 24.8% | 45.7% | -20.9% | 7.8% | 24.8% |
| San Diego | 1296437.0 | 52.6% | 40.2% | 27.0% | +13.2% | 8.2% | 27.7% |
| San Marcos | 80709.0 | 48.5% | 29.3% | 40.6% | -11.3% | 9.1% | 24.8% |
| Santee | 53302.0 | 59.2% | 27.0% | 43.9% | -16.9% | 9.7% | 23.2% |
| Solana Beach | 12864.0 | 68.0% | 32.4% | 37.1% | -4.7% | 7.4% | 26.0% |
Question:
What is the percentage of registered voters in which the d-r spread is +10.4%?
Answer:
42.9%