context: In Suriname today, Dutch is the sole official language, and over 60 percent of the population speaks it as a mother tongue. Dutch is the obligatory medium of instruction in schools in Suriname, even for non-native speakers. A further twenty-four percent of the population speaks Dutch as a second language. Suriname gained its independence from the Netherlands in 1975 and has been an associate member of the Dutch Language Union since 2004. The lingua franca of Suriname, however, is Sranan Tongo, spoken natively by about a fifth of the population.
question: సురినామ్ ఏ సంవత్సరం డచ్ భాషా యూనియన్లో చేరింది?
answers: 2004