Task: Question Understanding
Input (English): Passage: The Treaty of Karlowitz, signed in January 1699, confirmed the Venetian possession of Kephalonia, and the Morea with the island of Aigina, which became organized as the "Kingdom of the Morea" , divided into four provinces: Romania, with seat at Nafplion , Laconia, with seat at Monemvasia , Messenia, with seat at Navarino, and Achaea, with seat at Patras . The war however had created a demographic and economic crisis in the Peloponnese. According to the first census conducted by the Venetians, there were 86,468 people in the peninsula compared to a pre-war population of around 200,000. Although the Venetians managed to restore some prosperity - the population allegedly rose to some 250,000 by 1708, probably driven by immigration - they failed to win the trust of their Greek Orthodox subjects, who were used to a relative autonomy under the Turks and resented the Venetian bureaucracy. The Venetians also launched a great fortification project throughout the Morea, whose results can still be seen today. Nevertheless, Venice itself was too weakened to effectively assert its authority, and in 1715 a swift Ottoman campaign  reclaimed the Morea.
Question: How many years after the Treaty of Karlowitz was signed did the population allegedly rise to 250000?
Output (English): number