Does every house have a GFI?

Excuse me, as a professional practitioner in the field of finance and with a growing interest in home improvements, I've often wondered about electrical safety measures in residential buildings. Specifically, I'm curious about Ground Fault Interrupters (GFIs). Could you possibly enlighten me on whether every house nowadays is equipped with a GFI? I understand that GFIs play a crucial role in preventing electrical shocks and fires, and as such, I'm keen to know if this safety feature is a standard in modern homes. Thank you for your time and insight.