最近在听有声书。已经听到了最后一本的近一半。忽然想统计一下数据：
| title | word count | audio book length | audio book minutes | words per minute | read time | read time minutes | words per minute | word per minute diff |
| Harry Potter and the Philosopher’s Stone | 76,944 | 08:22:22 | 502 | 153.27 | ||||
| Harry Potter and the Chamber of Secrets | 85,141 | 09:42:36 | 583 | 146.04 | ||||
| Harry Potter and the Prisoner of Azkaban | 107,253 | 12:02:45 | 723 | 148.34 | 10:42:00 | 642 | 167.06 | -18.72 |
| Harry Potter and the Goblet of Fire | 190,637 | 20:55:36 | 1,256 | 151.78 | 20:39:00 | 1,239 | 153.86 | -2.08 |
| Harry Potter and the Order of the Phoenix | 257,045 | 28:51:11 | 1,731 | 148.50 | 22:39:00 | 1,359 | 189.14 | -40.65 |
| Harry Potter and the Half-Blood Prince | 168,923 | 20:33:36 | 1,234 | 136.89 | 16:12:00 | 972 | 173.79 | -36.90 |
| Harry Potter and the Deathly Hallows | 198,227 | 24:03:07 | 1,443 | 137.37 | 19:34:00 | 1,174 | 168.85 | -31.48 |
这里读书时间是我用一个APP统计的。前两本书没有统计。
可以看见，最长的一本书是凤凰社，长度差不多是最短的第一本书的三倍。这也是我最不喜欢的一本。读书普遍比念书快每分钟可以多读二三十个字，但不知为何火焰杯的速度差不多，也许是我统计出错了？
从这些数字中还可以得到什么结论？