Are Threats Against Obama a 400 Percent Increase From Previous Presidents?

I think any threat should be taken seriously. However it appears someone is getting their facts wrong.

I was watching something regarding this on CNN yesterday. The reporter made the point that the Secret Service told him that though there was uptick in threats after the swearing bit it quickly levleed off and currents threats against Obama are at the same level as the last two Presidents. So what is it?