During the Ottoman period, the citys population of Ottomans Muslims (including those of Turkish people and Albanians origin, as well as Bulgarian Muslim and Greek Muslim convert origin) grew substantially. According to the 1478 census Selânik (), as the city came to be known in Ottoman Turkish, had 6,094 Greek Orthodox households, 4,320 Muslim ones, and some Catholic. No Jews were recorded in the census suggesting that the subsequent influx of Jewish population was not linked to the already existing Romaniote Jews community. Soon after the turn of the 15th to 16th century, however, nearly 20,000 Sephardic Jews immigrated to Greece from the Iberian Peninsula following their expulsion from Spain by the 1492 Alhambra Decree. By c. 1500, the number of households had grown to 7,986 Greek ones, 8,575 Muslim ones, and 3,770 Jewish. By 1519, Sephardic Jewish households numbered 15,715, 54% of the citys population. Some historians consider the Ottoman regimes invitation to Jewish settlement was a strategy to prevent the ethnic Greek population from dominating the city.
Question: How many different populations lived in Selânik by c. 1500?
Answer: 3