2. Number of Conditions per RFC

Conditions	iCalendar (IETF RFC 2445)	iMIP (IETF RFC 2446)	iTIP (IETF RFC 2447)
`MUST`	159	195	16
`REQUIRED`	17	67	2
`MUST NOT`	55	60	0
`SHALL`	14	0	0
`SHALL NOT`	1	0	0
`SHOULD`	39	36	7
`SHOULD NOT`	6	2	0
`MAY`	79	217	7
`MAY NOT`	2	5	0