How many seconds are there in a decade? - Answers

315,532,800 or 315,619,200 seconds in a decade. Depending on whether the decade contains two leap years, or three (both is possible!)... (60*60*24*365*10) + (60*60*24*2 or 3) 10 years of 365 days + 2 or 3 days for leap years. Still, you might be off by a few leap seconds. These are inserted (or removed) because the earth is not as precise a timekeeper as cesium. The decade beginning 1/1/1970 added 8 leap seconds. The decade beginning 1/1/1980 brought 6. The next decade brought 7, and the decade beginning 1/1/2000 had only 2. The average decade seems to get about 6 of these things, but only time will tell how many we will see in the future.