What increases the risk of rollover crashes in 15-passenger vans?

We know from national statistics that 15-passenger vans are 3 times more likely to roll over than a passenger vehicle that carries 5 or less people. The reason for that is, when you load the passenger van with 10 or more people and their cargo, it shifts the center of balance to the back of the van. The stability is lost or compromised. Most new vehicles, and even passenger vans, are equipped with electronic stability control systems, but older 15-passenger vans do not have those systems in place, so you lose balance and you don't have the system to warn you of that. That is why there are more rollovers of 15-passenger vans.