Although the United States has no de jure official language, English is the dominant language of business, education, government, religion, media, culture, civil society, and the public sphere. Virtually all state and federal government agencies and large corporations use English as their internal working language, especially at the management level. Some states, such as New Mexico, provide bilingual legislated notices and official documents, in Spanish and English, and other commonly used languages. By 2015, there was a trend that most Americans and American residents who are of Hispanic descent speak only English in the home.
Is there an answer to this question (If it cannot be answered, say "unanswerable"): By when did most Americans and American residents who are of Hispanic descent speak only Spanish in the home?
unanswerable