diff --git a/src/axes.jl b/src/axes.jl
index 303e24db..debb3773 100644
--- a/src/axes.jl
+++ b/src/axes.jl
@@ -365,7 +365,7 @@ function expand_extrema!(sp::Subplot, d::KW)
 
         bw = d[:bar_width]
         if bw == nothing
-            bw = d[:bar_width] = _bar_width * ignorenan_minimum(filter(x->x>0,diff(data)))
+            bw = d[:bar_width] = _bar_width * ignorenan_minimum(filter(x->x>0,diff(sort(data))))
         end
         axis = sp.attr[Symbol(dsym, :axis)]
         expand_extrema!(axis, ignorenan_maximum(data) + 0.5maximum(bw))