Gaelic continues to decline in its traditional heartland. Between 2001 and 2011, the absolute number of Gaelic speakers fell sharply in the Western Isles (1,745), Argyll & Bute (694), and Highland (634). The drop in Stornoway, the largest parish in the Western Isles by population, was especially acute, from 57.5% of the population in 1991 to 43.4% in 2011. The only parish outside the Western Isles over 40% Gaelic-speaking is Kilmuir, Skye in Northern Isle of Skye at 46%. The islands in the Inner Hebrides with significant percentages of Gaelic speakers are Tiree (38.3%), Raasay (30.4%), Skye (29.4%), Lismore, Scotland (26.9%), Colonsay (20.2%), and Islay (19.0%).

Based on the above article, answer a question. How many in percent of people in Tiree don't speak Gaelic?
61.7