Change formula for multi-file proportion graph

I believe the denominator is incorrect and the float values can exceed 1.0

utils.py

@@ -472,9 +472,6 @@ def build_multifile_category_df(validNames, results, summaries, categories, cate
         try:
             catSummary, extraCats = su.calcCategories(currAnnotation, per_file_selections)
         except (UnboundLocalError, Exception):
-            # calcCategories can fail when a role contains a speaker with no
-            # segments in this annotation (e.g. assigned in quick succession
-            # before the UI has settled).  Skip this file for the summary.
             summaries[fn]["categories"] = ([], [])
             continue
         # Apply display names to raw speaker IDs in extraCats
@@ -492,10 +489,17 @@ def build_multifile_category_df(validNames, results, summaries, categories, cate
     for fn in validNames:
         summary, extras = summaries[fn]["categories"]
         theseCategories = categories + extras
+        # Use the annotation's actual span as denominator, falling back to
+        # results[fn][1]. This avoids >1.0 values when totalSeconds was
+        # truncated to int or is slightly shorter than the last segment end.
+        annotation_end = max(
+            (s.end for s in results[fn][0].itersegments()),
+            default=results[fn][1]
+        )
+        safe_total = max(annotation_end, results[fn][1], 1)
         for j, timeSlots in enumerate(summary):
-            df6_dict[theseCategories[j]].append(
-                sum(t.duration for _, t in timeSlots) / results[fn][1]
-            )
+            val = sum(t.duration for _, t in timeSlots) / safe_total
+            df6_dict[theseCategories[j]].append(min(val, 1.0))
         for category in allCategories:
             if category not in theseCategories:
                 df6_dict[category].append(0)