What are the most frequently used letters in English?

gistfile1.txt

(->> (slurp "ni2.txt")
     clojure.string/split-lines
     (map clojure.string/lower-case)
     (map #(map char %))
     flatten
     frequencies
     (map #(vector (key %) 
                   (read-string 
                     (format "%.2f" (* 100 (/ (val %) 2251877.0))))))
     (sort-by last)
     reverse)
     
;;  ([\e 10.43] [\i 8.91] [\a 8.83] [\o 7.57] [\r 7.13] [\n 7.03] 
;;   [\t 6.78] [\s 6.18] [\l 5.78] [\c 4.59] [\u 3.87] [\p 3.47] 
;;   [\m 3.13] [\d 3.02] [\h 2.85] [\y 2.29] [\g 2.09] [\b 1.79] 
;;   [\f 1.07] [\v 0.89] [\k 0.71] [\w 0.61] [\z 0.37] [\x 0.31] [\q 0.17] [\j 0.14])