You need to spend this many hours to get enough XP to move from this skill level to that skill level:  In general, once it levels off it's 200 hours per point for Mental skills, 400 hours per point for Physical skills.  Levels of EideticMemory will further halve the time needed for Mental Skills --- a character with two levels of EideticMemory generates an XP in a skill per 50 hours of teaching.

These times are doubled if you don't have a teacher.  If you don't have any study material at all, or are trying to invent a new skill, they are quadrupled.

<table border=1>
  <TR>
    <th>Mental Hours Spent</th>
    <th>Physical Hours Spent</th>
    <th>Easy Level</th>
    <th>Average Level</th>
    <th>Hard Level</th>
    <th>Very Hard Level</th>
  </tr>
  <tr>
    <td>100</td>
    <td>100</td>
    <td>Stat-1</td>
    <td>Stat-2</td>
    <td>Stat-3</td>
    <td>Stat-4</td>
  </tr>
  <tr>
    <td>200</td>
    <td>200</td>
    <td>Stat</td>
    <td>Stat-1</td>
    <td>Stat-2</td>
    <td>Stat-3</td>
  </tr>
  <tr>
    <td>400</td>
    <td>400</td>
    <td>Stat+1</td>
    <td>Stat</td>
    <td>Stat-1</td>
    <td>Stat-2</td>
  </tr>
  <tr>
    <td>800</td>
    <td>800</td>
    <td>Stat+2</td>
    <td>Stat+1</td>
    <td>Stat</td>
    <td>Stat-1</td>
  </tr>
  <tr>
    <td>1600</td>
    <td>1600</td>
    <td>Stat+3</td>
    <td>Stat+2</td>
    <td>Stat+1</td>
    <td>Stat</td>
  </tr>
  <tr>
    <td>2400</td>
    <td>3200</td>
    <td>Stat+4</td>
    <td>Stat+3</td>
    <td>Stat+2</td>
    <td>Stat+1</td>
  </tr>
  <tr>
    <td>3200</td>
    <td>4800</td>
    <td>Stat+5</td>
    <td>Stat+4</td>
    <td>Stat+3</td>
    <td>Stat+2</td>
  </tr>
  <tr>
    <td>+800</td>
    <td>+1600</td>
    <td>+1</td>
    <td>+1</td>
    <td>+1</td>
    <td>+1</td>
  </TR>
</table>

Also, note the rules on spending accumulated points through a TrainingMontage.


A SleepTeaching program allows the time you spend asleep to count as hours of study.  Nevertheless, SleepTeaching may not be used for more than half of the hours involved in a given advance.