Larger Tetras live longer... i think.
Try the website below.
My link<-- I often use this website.
Hagrid66
My mate has a planted tank with a large school of neons, he says about 20% are the originals from 2003 when he set it up, the rest range from 1 to 6. My oldest fish was a tank kept goldie who was 16 won him from a fair when i was young, most people were surprising he reached more than 2 weeks