diff --git a/skimage/filter/rank/percentile_cy.pyx b/skimage/filter/rank/percentile_cy.pyx
index 8fad59c5..5989cdca 100644
--- a/skimage/filter/rank/percentile_cy.pyx
+++ b/skimage/filter/rank/percentile_cy.pyx
@@ -161,14 +161,14 @@ cdef inline double _kernel_percentile(Py_ssize_t* histo, double pop, dtype_t g,
     cdef Py_ssize_t sum = 0
 
     if pop:
-        if p0 == 0:  # make sure p0 == 0 returns the minimum filter
-            for i in range(max_bin):
+        if p0 == 1:  # make sure p0 = 1 returns the maximum filter
+            for i in range(max_bin - 1, -1, -1):
                 if histo[i]:
                     break
         else:
             for i in range(max_bin):
                 sum += histo[i]
-                if sum >= p0 * pop:
+                if sum > p0 * pop:
                     break
         return i
     else: