[MSDN Library April 2000] LookupType 1: Single Substitution Subtable (100%)

MSDN Library - April 2000 > Specifications > Applications > TrueType Open Font > 3. The Glyph Substitution Table (GSUB)

[MSDN Library April 2000] LookupType 2: Multiple Substitution Subtable (96.1111111111111%)

MSDN Library - April 2000 > Specifications > Applications > TrueType Open Font > 3. The Glyph Substitution Table (GSUB)

[MSDN Library April 2000] LookupType 4: Ligature Substitution Subtable (96.1111111111111%)

MSDN Library - April 2000 > Specifications > Applications > TrueType Open Font > 3. The Glyph Substitution Table (GSUB)

[MSDN Library April 2000] LookupType 3: Alternate Substitution Subtable (95.6521739130435%)

MSDN Library - April 2000 > Specifications > Applications > TrueType Open Font > 3. The Glyph Substitution Table (GSUB)

[MSDN Library April 2000] LookupType 5: Contextual Substitution Subtable (94.6808510638298%)

MSDN Library - April 2000 > Specifications > Applications > TrueType Open Font > 3. The Glyph Substitution Table (GSUB)