Gallup va entrevistar 150.000 adults a 148 països, fent preguntes com "Vas somriure o riure ahir?" o "Vas aprendre o fer quelcom interessant ahir?" per a construir un índex d'experiència positiva.
Gallup interviewed 150,000 adults in 148 countries, asking such questions as, "Did you smile or laugh yesterday?" and "Did you learn or do something interesting yesterday?" to build a positive-experience index.