Leap year on cover from USA

I received one more cover dedicated to Leap year, but this time from USA. A leap year is a calendar year that contains an additional day added to keep the calendar year synchronized with the astronomical year or seasonal year. Because astronomical events and seasons do not repeat in a whole number of days, calendars that have the same number of days in each year drift over time with respect to the event that the year is supposed to track. By inserting an additional day or month into the year, the drift can be corrected.On this cover from Miami you can see stamps dedicated to Year of the Rat and in the middle definitive stamp with American eagle.

Inside cover was this FDC dedicated to wild orchids. There are more than 30,000 species of wild orchids in the world. And these two stamps are from set of ten stamps which shows orchid species from USA.

Thank you, Mike!