Probably linked to the fixes to T135502
```
Notice: Undefined offset: 3 in /data/project/heritage/heritage/api/includes/Statistics.php on line 112
Call Stack:
0.0116 668104 1. {main}() /data/project/heritage/heritage/api/api.php:0
0.0966 1648256 2. ApiMain::dispatch() /data/project/heritage/heritage/api/api.php:36
0.1174 1956560 3. ApiMonuments->executeModule() /data/project/heritage/heritage/api/includes/ApiMain.php:39
0.1415 2201328 4. ApiMonuments->statistics_db() /data/project/heritage/heritage/api/includes/ApiMonuments.php:75
0.1423 2203664 5. Statistics->retrieveReport() /data/project/heritage/heritage/api/includes/ApiMonuments.php:370
4.7166 2386024 6. Statistics::invertIdx() /data/project/heritage/heritage/api/includes/Statistics.php:84
Notice: Undefined offset: 2 in /data/project/heritage/heritage/api/includes/Statistics.php on line 112
Call Stack:
0.0116 668104 1. {main}() /data/project/heritage/heritage/api/api.php:0
0.0966 1648256 2. ApiMain::dispatch() /data/project/heritage/heritage/api/api.php:36
0.1174 1956560 3. ApiMonuments->executeModule() /data/project/heritage/heritage/api/includes/ApiMain.php:39
0.1415 2201328 4. ApiMonuments->statistics_db() /data/project/heritage/heritage/api/includes/ApiMonuments.php:75
0.1423 2203664 5. Statistics->retrieveReport() /data/project/heritage/heritage/api/includes/ApiMonuments.php:370
4.7166 2386024 6. Statistics::invertIdx() /data/project/heritage/heritage/api/includes/Statistics.php:84
```
---
Example url: https://tools.wmflabs.org/heritage/api/api.php?action=statistics&stcountry=ua&format=html (notoe that this does not appear if you [[ https://tools.wmflabs.org/heritage/api/api.php?action=statistics&stcountry=ua&format=html&limit=10 | append limit=10 ]].