steam
I've been on steam since Jan 21 of 2004. I have 112 XP left to reach level 11 (out of a total of 200). With 11 years, I earned 550 XP, which should be enough for both what I have left on level 10, level 11 and 12 (200 XP per level until level 21). I didn't gain any XP AT ALL. I'm still have 112 left to level.
In other words, with this badge, mathematically speaking, I should now be level 13, but what's the problem?
I'll explain this in two parts:
The Green box highlights a F2P game utilizing a Micro-Transaction model. As you can see, it says "no card drops remaining". But I can get more if I purchase any item from the store in increments of $9.00 (ie I spend $18.00, I get 2 cards). Thus, for games like TF2, you don't necessarily have to trade to get a badge Lvl2+ (but is advisable).
If you look at the red box, however, since Bit.Trip Runner2 is a paid game, it features a permanent drop counter. Meaning, once the 3 card drops I have left are given, there will be no more card drops, by playing the game. Once you've received all possible card drops, you may receive a booster pack, which contains 3 cards, either basic or foil. The rate at which these booster packs appear in your inventory depends on your steam level and as game badges are crafted by the community. Keep this in mind if you plan to sell or trade those cards out.
Associated question: How do trading card booster packs drop?
I have first hand confirmation of levels 1 through 5. According members in the Steam forums there exist a Foil badge, Gaming Globetrotter. I have yet to confirm its existence as I have no foil badges.
Best Answer
The years of service badge upgrades the same way as game badges. The value shown is the total XP earned across all unlocked levels of the badge combined.
The most recent badge doesn't actually give you 550 XP, that's just your new total with the addition of the new badge. So whatever the difference between your total for 11 years and 10 years is, that's how much XP you earned from the new badge.
EDIT: It's 50 XP per level for this particular badge. So you earned 50 XP, not 550.