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.
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.