I spent a bit of time digging into this. I looked at the past 365 of questions posted on the site to get the numbers. Here is what I found:
Over the past 365 days, there were 6,534 questions asked, of these:
- 3,313 have received at least one close vote or flag,
- 2,135 questions were closed,
- 1,534 of the questions had at least one close vote or flag that aged away, and
- of the questions that were closed, 139 were reopened by the community
Breaking these numbers down by close reasons, here are the total number of *flags/votes on questions, and then total number of those votes/flags that aged away by close reason:
+---------------------------------------------------------------------------------------+---------------+-------------------------+
| Flag/Close Vote Reason | # Flags / CVs | # Flags / CVs Aged Away |
+---------------------------------------------------------------------------------------+---------------+-------------------------+
| Too broad | 4394 | 881 |
| Primarily opinion-based | 2892 | 601 |
| Off-topic This question does not appear to be about **worldbuilding**, within the sco | 2393 | 424 |
| Unclear what you're asking | 2108 | 389 |
| Off-topic You are asking questions about a story set in a world instead of about buil | 1202 | 322 |
| Duplicate | 1196 | 186 |
| Off-topic Other (add a comment explaining what is wrong) | 164 | 48 |
| Off-topic This question belongs on another site in the Stack Exchange network | 62 | 1 |
+---------------------------------------------------------------------------------------+---------------+-------------------------+
I also looked at the questions that had been closed and then received reopen votes/flags to see how many of them aged away.
+---------------------------------------------------------------------------------------+----------------+--------------------------+
| Close Reason | # Reopen Votes | # Reopen Votes Aged Away |
+---------------------------------------------------------------------------------------+----------------+--------------------------+
| Too broad | 152 | 4 |
| Off-topic This question does not appear to be about **worldbuilding**, within the sco | 111 | 0 |
| Unclear what you're asking | 111 | 3 |
| Primarily opinion-based | 98 | 9 |
| Off-topic You are asking questions about a story set in a world instead of about buil | 60 | 2 |
| Duplicate | 52 | 2 |
| Off-topic Other (add a comment explaining what is wrong) | 4 | 0 |
| Off-topic This question belongs on another site in the Stack Exchange network | 3 | 0 |
+---------------------------------------------------------------------------------------+----------------+--------------------------+
Far fewer reopen votes were cast, so even less of them aged away, but over the past year, approximately 19% of close votes/flags aged away.
As requested here are the comparisons to the other sites on the network for Pct Aged Away:
+---------------------------------------------------+---------------+
| Site Name | Pct Aged Away |
+---------------------------------------------------+---------------+
| Freelancing Stack Exchange | 54.18 |
| Esperanto Language Stack Exchange | 47.58 |
| Artificial Intelligence Stack Exchange | 45.88 |
| Martial Arts | 42.35 |
| Sustainable Living | 40 |
| Stack Overflow | 37.59 |
| Homebrew | 33.33 |
| Coffee Stack Exchange | 31.86 |
| Linguistics | 30.97 |
| Super User | 29.88 |
| Health Stack Exchange | 29.16 |
| Graphic Design | 28.75 |
| 3D Printing Stack Exchange | 28.54 |
| Chinese Language and Usage | 28.16 |
| Mythology Stack Exchange | 26.9 |
| History of Science and Mathematics Stack Exchange | 26.53 |
| Audio-Video Production | 26.31 |
| Programmers | 25.67 |
| Arduino Stack Exchange | 24.88 |
| Tridion Stack Exchange | 24.75 |
| Computer Science | 24.64 |
| Software Recommendations Stack Exchange | 24.39 |
| Amateur Radio Stack Exchange | 24.22 |
| Photography | 24.11 |
| Open Data Stack Exchange | 23.95 |
| Project Management | 23.9 |
| Jewish Life and Learning | 23.78 |
| Open Source Stack Exchange | 23.51 |
| Motor Vehicle Maintenance and Repair | 22.96 |
| Emacs Stack Exchange | 22.77 |
| Server Fault | 22.65 |
| Game Developers | 22.65 |
| German Language and Usage | 22.24 |
| elementary OS Stack Exchange | 22.07 |
| Beer Stack Exchange | 21.95 |
| Quantitative Finance | 21.69 |
| Startups Stack Exchange | 21.4 |
| Pets Stack Exchange | 21.26 |
| Law Stack Exchange | 21.17 |
| Reverse Engineering Stack Exchange | 21.11 |
| Expatriates Stack Exchange | 20.97 |
| Literature | 20.75 |
| Economics | 20.69 |
| Korean Language Stack Exchange | 20.59 |
| Ebooks Stack Exchange | 20.41 |
| Cognitive Sciences | 19.99 |
| Worldbuilding Stack Exchange | 19.75 |
| Latin Language Stack Exchange | 19.75 |
| The Great Outdoors | 19.66 |
| CiviCRM Stack Exchange | 19.08 |
| Cooking | 18.97 |
| Moderators Stack Exchange | 18.75 |
| Music Fans Stack Exchange | 18.16 |
| Philosophy | 17.7 |
| WordPress | 17.16 |
| Buddhism Stack Exchange | 17.14 |
| Chess | 17.11 |
| Politics | 17.11 |
| Arts & Crafts Stack Exchange | 17.11 |
| Lifehacks Stack Exchange | 17.06 |
| Writers | 16.75 |
| Theoretical Computer Science | 16.62 |
| Raspberry Pi | 16.18 |
| Retrocomputing Stack Exchange | 15.98 |
| Sitecore Stack Exchange | 15.59 |
| Internet of Things Stack Exchange | 15.55 |
| Computer Graphics Stack Exchange | 15.49 |
| Gardening and Landscaping | 15.31 |
| Biology | 15.3 |
| Stack Overflow на русском | 15.2 |
| Woodworking Stack Exchange | 15.18 |
| ExpressionEngine | 15.15 |
| Bicycles | 14.91 |
| Russian Language and Usage | 14.86 |
| Aviation Stack Exchange | 14.58 |
| Astronomy | 14.57 |
| Language Learning Stack Exchange | 14.14 |
| Sports | 14.09 |
| English Language Learners | 13.94 |
| Apple | 13.67 |
| Sound Design Stack Exchange | 13.63 |
| Blender Stack Exchange | 13.62 |
| Islam | 13.59 |
| Computational Science | 13.28 |
| Board and Card Games | 13.16 |
| Earth Science Stack Exchange | 13.06 |
| Hinduism Stack Exchange | 12.86 |
| Skeptics | 12.75 |
| Engineering Stack Exchange | 12.64 |
| Puzzling Stack Exchange | 12.41 |
| Movies | 12.38 |
| Personal Productivity | 12.33 |
| Japanese Language and Usage | 12.1 |
| Personal Finance and Money | 12.09 |
| Bitcoin | 12.01 |
| Windows Phone | 11.83 |
| Parenting | 11.68 |
| Android Enthusiasts | 11.63 |
| Software Quality Assurance and Testing | 11.62 |
| Biblical Hermeneutics | 11.5 |
| Role-playing Games | 11.29 |
| French Language and Usage | 10.92 |
| The Workplace | 10.87 |
| Vi and Vim Stack Exchange | 10.84 |
| MathOverflow | 10.76 |
| Christianity | 10.75 |
| Signal Processing | 10.66 |
| Science Fiction | 10.61 |
| Travel | 10.61 |
| Stack Overflow em Português | 10.11 |
| Ethereum Stack Exchange | 10.1 |
| Web Apps | 10.07 |
| Home Improvement | 9.95 |
| Mathematics | 9.56 |
| Fitness and Nutrition | 9.51 |
| Mathematics Educators Stack Exchange | 9.51 |
| Space Exploration Stack Exchange | 8.98 |
| Statistical Analysis | 8.96 |
| Portuguese Language Stack Exchange | 8.82 |
| Academia | 8.76 |
| History | 8.65 |
| Joomla Stack Exchange | 8.6 |
| Data Science Stack Exchange | 8.36 |
| Ubuntu | 8.26 |
| Code Review | 8.08 |
| Spanish Language and Usage | 7.92 |
| Patents | 7.81 |
| English Language and Usage | 7.8 |
| Salesforce | 7.8 |
| SharePoint | 7.76 |
| Stack Overflow en español | 7.74 |
| Genealogy and Family History | 7.5 |
| Hardware Recommendations Stack Exchange | 7.46 |
| Monero Stack Exchange | 7.44 |
| Database Administrators | 7.31 |
| Magento | 7.28 |
| Gaming | 7.26 |
| LEGO® | 7.19 |
| Italian Language Stack Exchange | 7.14 |
| Poker | 7.01 |
| IT Security | 6.91 |
| User Experience | 6.86 |
| Craft CMS Stack Exchange | 6.69 |
| Physics | 6.66 |
| Code Golf | 6.6 |
| Musical Practice and Performance | 6.39 |
| Drupal Answers | 6.3 |
| Electronics and Robotics | 6.27 |
| Mathematica | 6.22 |
| Anime and Manga | 5.89 |
| Unix and Linux | 5.64 |
| Robotics | 5.2 |
| Cryptography | 5.06 |
| Chemistry | 4.65 |
| GIS | 4.62 |
| Stack Apps | 4.4 |
| Webmasters | 3.52 |
| TeX - LaTeX | 3.32 |
| Tor Stack Exchange | 3.18 |
| Network Engineering Stack Exchange | 1.44 |
+---------------------------------------------------+---------------+