The page below shows the media peformance of Python (the fastest in these of PHP/Ruby/Python) as 49.73 times slower than the fastest compiled language. The seems pretty much between 10 and 100 to me.

http://shootout.alioth.debian.org/u64q/which-programming-lan...

 	compare 2	 |-	 |---	 25%	median	 75%	 ---|	 -|

Fortran Intel 1.00 1.00 1.00 1.01 1.35 1.87 7.84 C GNU gcc 1.00 1.00 1.01 1.21 1.55 2.36 4.97 C++ GNU g++ 1.00 1.00 1.10 1.26 1.68 2.28 2.28 ATS 1.00 1.00 1.24 1.45 2.30 3.90 7.24 Ada 2005 GNAT 1.04 1.04 1.22 1.51 1.84 2.76 4.81 Java 7 -server 1.40 1.40 1.59 1.90 2.14 2.97 4.76 Scala 1.38 1.38 1.90 2.76 3.43 5.72 10.21 Haskell GHC 1.53 1.53 2.60 2.80 4.36 7.00 15.15 Go 1.29 1.29 2.12 2.85 6.90 14.08 24.05 C# Mono 1.60 1.60 2.62 3.08 7.12 13.88 14.21 Lisp SBCL 1.12 1.12 1.81 3.40 4.24 7.89 11.20 OCaml 1.18 1.18 1.76 3.75 4.87 9.24 9.24 Pascal Free Pascal 1.53 1.53 2.47 4.37 7.49 15.03 24.20 Clojure 2.02 2.02 3.50 4.99 8.44 14.81 14.81 F# Mono 2.97 2.97 3.16 5.33 8.92 17.57 37.80 Racket 1.22 1.22 5.06 6.86 11.04 19.99 59.08 Erlang HiPE 5.17 5.17 7.99 10.79 15.44 26.61 41.54 Erlang 5.40 5.40 14.20 22.73 30.09 53.91 218.10 Python 3 1.22 1.22 9.25 49.73 68.86 131.37 131.37 PHP 1.90 1.90 10.29 50.17 83.42 193.10 260.90 Ruby 1.9 4.67 4.67 11.74 53.29 101.33 235.71 356.61 Ruby JRuby 5.75 5.75 26.67 58.81 115.06 247.65 266.51 Perl 4.00 4.00 22.61 103.29 126.82 225.35 225.35