I'm a stoopid level 5...what is NA?

I'm still trying to figure out the fastest way to move up levels...

Name: Megatron Gold Bars: 25
Level: 5 Exp: 67%
Money: $152,158 Health: 300/300
Property: Penthouse Suite
Property Cost: $45,000,000

Player Statistics: Strength: 671 [Ranked: 2215] Speed: 588 [Ranked: 2136]
Defense: 565 [Ranked: 2096] Employment Skills: 93 [Ranked: 3779]
Brain Power: 77 [Ranked: 2938] Total stats: 1,994 [Ranked: 2256]