The exact number of speakers in Greece is difficult to ascertain, with estimates ranging between 20,000 and 250,000. Jacques Bacid estimates in his 1983 book that "over 200,000 Macedonian speakers remained in Greece". Other sources put the numbers of speakers at 180,000 220,000 and 250,000, whereas Yugoslav sources vary, some putting the estimated number of "Macedonians in Greek Macedonia" at 150,000–200,000 and others at 300,000. The Encyclopædia Britannica and the Readers Digest World Guide both put the figure of ethnic Macedonians in Greece at 1.8% or c.200,000 people, with the native language roughly corresponding with the figures. The UCLA also states that there are 200,000 Macedonian speakers in Greece. A 2008 article in the Greek newspaper Eleftherotypia put the estimate at 20,000.
Question: By how many speakers do estimates vary?
Answer: 230000