Researchers from several institutions teamed up to estimate the trajectory of depressive symptoms across an entire adult life span. To complete the tall task, they used personal assessments from 2,320 participants to track the ups and downs of gloom by a myriad of demographics including sex, ethnicity, education level and overall physical health.  After looking at more than 30 years of data, researchers were able to nail down a lifetime course of happiness: depressive symptoms were highest in young adulthood, decreased across middle adulthood, and increased again into older adulthood, with the lowest dip occurring around age 66, on average. Does that mean 66 is the happiest year of your life? Not so fast, say the investigators. “I wouldn’t say we found the happy age, but rather the age when people are less sad,” says researcher Angelina Sutin, PhD, assistant professor at Florida State University College of Medicine.  Older adults reported more symptoms of depression, but also greater well-being with age. “Taken together, the evidence suggests we become more emotional with age, and with greater complexity than younger and middle-aged adults.” More from Prevention: 50 Things That Get Better With Age The results are congruent with a recent Harris Interactive poll which found Americans 50 years and older are more likely to be “very happy” than younger age groups. Experts link it to resilience and the long-gone need to be perfect on the outside, but depression can happen at any time—even during the happy age.  “I expected to see a bigger effect with disease and disability,” says Sutin, who noted even the most healthy participants followed the same trajectory of sadness. “This suggests that other factors, like death of a spouse and loss of social support networks, may have more of an impact on depression in old age than physical health.” You are a complex creature—emotional ups and downs are about as normal as a change in weather. But if you’ve got a sunny disposition, run with it. You’re in your prime! Now, what are you going to do with it? More from Prevention: 12 Ways To Have More Fun