The are many other units of time, the month, the second, the fortnight etc. The way powers of ten work for each unit of time, there is a unique power of ten 10-to-the-nth so that 10-to-the-nth units of time is between 10 and 100 years. For example 100 months is 8 1/3 years (less than 10 years), 1000 months is 83 1/3 years (between 10 and 100) and 10,000 months is 833 1/3 years (more than 100 years). So for months, 1000 months is between 10 and 100 years. Many more people can celebrate their 1000th month birthday, then their 100th.
This gives several "party opportunities" for people between the ages of 18-33. (Like celebrating a 1000-month birthday, only that would be for someone 83.3 years old.) What are they?
1,000 sec is 16 2/3 minutes 10,000 sec is 2 7/9 hours 100,000 sec is 1.16 days 1,000,000 sec is 11.6 days 1,000,000,000 sec is 31.7 years 1,000 min is 16 2/3 hours 10,000 min is 6.94 days 1,000,000 min is 1.9 years 10,000,000 min is 19.0 years 1,000,000,000 min is 1901 years 1,000 hours is 41 2/3 days 10,000 hours is 11.4 years 1,000,000 hours is 114 years 1,000 days is 2.7 years 10,000 days is 27.4 years 1,000,000 days is 2738 years 100 weeks is 1.9 years 1000 weeks is 19.2 years 100 fortnights is 3.8 years 1000 fortnights is 38.3 years 1000 months is 83 1/3 years. 10 olympiads is 40 years 10,000 hours 11.4 years 10,000,000 min 19.0 years 1,000 weeks 19.2 years 10,000 days 27.4 years 1,000,000,000 sec is 31.7 years 1,000 fortnights is 38.3 years 10 olympiads is 40 years 1,000 months is 83.3 years