Of course not. You're a moron. And they count on that, so they use big numbers to confuse you. Clearly 31 is a very big number for you.
You know sometimes I need a security detail for my events, I hire two agencies. Sometimes my guests are important, they have their own security. Just off the top of my head (and I'm nobody) I can name 14 different agencies at pretty much any given sporting event or concert. And that's me, I'm stupid. There's probably at least another 100. And that's for a stupid event. This was pretty serious and involved an entire state, not to mention the observers.
There's also probably 147 different types of guns, shoes, vehicles, tires, whatever.
tl;dr? Posting #'s is fucking retarded without any context. And I sure as shit hope other "Agencies" sent observers despite the insinuation that it's a BIG CONFUSING NUMBER so morons don't criticize them for trying to learn something from this situation when we deal with it next time. And there will be a next time, because.... #'s.