@Riot Change of LP system a bit?

So, I don't know how often this happens to others, but here's the thing. I will play a match of ranked, win and gain an average of about 18 LP, but if I lose, I will lose an average of about 21 LP. Why is that? Better example, in my last 4 ranked games, I have won 3, and lost 1. How much LP do I have left? 28. 28 LP after winning 3 games, and losing just 1. I mean, what is that? If Im winning 18 a game, and maybe a 14, I would have 50 LP, but then I lose one game, and I would have lost 22 LP. It may not seem that big of an increment, but those points add up after just 3 games you were to have lost. IF you lose an extra 3 or 4 LP a game, for 3 games, you would have lost almost a whole extra game. I don't understand that. I WOULD understand if I was to win a match, gain 15 LP, and then if I lose a match, I would lose those same 15 LP. After that, if I lost a second time in a row, I would lose about 18-20 LP. But it wouldnt go past that much. Basically, I win a certain amount of LP, depending on the MMR of each team, then if I lost the next match, I should lose that same amount, or very close to it. By very close I mean +/-1. I just find it a bit much to be able to win 3 or 4 games, only to have almost all that LP gone, in just 2 lost games.