静态文本框中，改变CreateFont第一个参数为什么字的大小没有改变？

以下是代码：CFont font;
VERIFY(font.CreateFont(
   20,                        // nHeight
   0,                         // nWidth
   0,                         // nEscapement
   0,                         // nOrientation
   FW_DEMIBOLD,                 // nWeight
   FALSE,                     // bItalic
   FALSE,                     // bUnderline
   0,                         // cStrikeOut
   ANSI_CHARSET,              // nCharSet
   OUT_DEFAULT_PRECIS,        // nOutPrecision
   CLIP_DEFAULT_PRECIS,       // nClipPrecision
   DEFAULT_QUALITY,           // nQuality
   DEFAULT_PITCH | FF_SWISS,  // nPitchAndFamily
   _T("Arial")));                 // lpszFacename
GetDlgItem(IDC_STATIC_TITLE)->SetFont(&font);