Tasha, you're getting good advice from almost everyone here. But I think Kyle caught something that others didn't.
Instead of repeating the tips already given, I'd like to discuss the TIMING of your vault ... during your swing and extension.
You swing to a pike, then pause, then shoot out of the pike. I doubt that that's your intention. I'll guess that you're really trying to use the Petrov Model. And for your age and PR, you're doing it moderately well. However, the best tip that I can give you is to try to continue your swing right on up and through your extension ... in one continuous motion. That's the "continuous chain", and that's the Petrov way.
You may not recognize that you do this, but you swing to a pike position (instead of a rockbacked tuck position), then you pause, then you shoot out of that, as you flag over the bar.
I'll guess that you're probably a good gymnast, and you can do a kip fairly well on the uneven bars.
At least that's what it looks like you're doing ... kipping up and over the bar. 
So first of all, it's not all bad. It's not as bad as the tuck/shoot. At least it's a pike/shoot. Brad Walker does some of this, so it ain't all bad.
But he doesn't pause nearly as long as you do.So ask yourself these 2 questions:
1. Why am I pausing?
2. Why am I flagging out over the bar?
Think about it.
The answer lies in what Kyle said.

So what can you do about it? And how will that help?
I could just tell you what I think, but perhaps if you think about it awhile, then it might sink in better.
I'll get back to you as soon as you tell me what you thought about, and how you think you can improve this part of your vault.
Kirk
Should I start dropping the tip when I'm around my third left? Thanks!