Career Builder just released its annual survey on office romances. And if you’re alone this Valentine’s Day, you might want to think about staying late tonight . . . because it’s the most common way relationships at work start.

12% of people who’ve dated a coworker say it started because of a late night at work. Having drinks after work, and running into each other outside of work tied for second with 10% . . . lunch was third with 9% . . . and another 9% said it was love at first sight.

Here are six more stats from the survey . . .

1. 37% of us have dated a coworker at least once.

2. 33% of office romances eventually lead to marriage. Which seems high, but they asked the same question last year, and it was 30%.

3. 23% of people who’ve dated a coworker say it was someone in a higher position than them.

4. 33% had to keep their relationship secret.

5. 17% of office relationships involve someone who’s already married.

6. And 5% of people who’ve dated a coworker had to leave their job because of it.