Update README.md

README.md

@@ -75,7 +75,8 @@ Each question entry is arranged as follows. **Note that for visual questions, th
         "instructions": instructions,
         "url": url of the input image,
         "extra_input_figure_ids": ids of the extra input figures,
-        "extra_input_figure_bboxes": bbox of the extra input figures, in [x,y,w,h] format w/o normalization.
+        "extra_input_figure_bboxes": bbox of the extra input figures, in [x,y,w,h] format w/o normalization,
+        "data_fact": data fact of the question, only for text-based questions,
         "difficulty": difficulty level,
         "chart_type": chart_type,
 }