6502 cycle times

I put this spreadsheet together because I didn't like the way the timing information was organized in other places. Some mnemonic/addressing mode combinations do not have an opcode and are left blank because they are not legal instructions. I may add the illegal opcodes later. Cells marked with "+" mean add one cycle if a page boundary is crossed.

Mnemonic	Description	IMP	IMM	ZP	ZP,X	ZP,Y	ABS	ABS,X	ABS,Y	IND	IND,X	IND,Y	ACC
ADC	ADd with Carry		2	3	4		4	4+	4+		6	5+
AND	bitwise AND with accumulator		2	3	4		4	4+	4+		6	5+
ASL	Arithmetic Shift Left			5	6		6	7
BIT	test BITs			3			4
BRK	BreaK	7
CMP	CoMPare accumulator		2	3	4		4	4+	4+		6	5+
CPX	ComPare X register		2	3			4
CPY	ComPare Y register		2	3			4
DEC	DECrement memory			5	6		6	7
EOR	bitwise Exclusive OR		2	3	4		4	4+	4+		6	5+
INC	INCrement memory			5	6		6	7
JMP	JuMP						3			5
JSR	Jump to SubRoutine						6
LDA	LoaD Accumulator		2	3	4		4	4+	4+		6	5+
LDX	LoaD X register		2	3		4	4		4+
LDY	LoaD Y register		2	3	4		4	4+
LSR	Logical Shift Right			5	6		6	7					2
NOP	No OPeration	2
ORA	bitwise OR with Accumulator		2	3	4		4	4+	4+		6	5+
ROL	Rotate Left			5	6		6	7					2
ROR	Rotate Right			5	6		6	7					2
RTI	ReTurn from Interrupt	6
RTS	ReTurn from Subroutine	6
SBC	SuBtract with Carry		2	3	4		4	4+	4+		6	5+
STA	Store Accumulator			3	4		4	5	5		6	6
STX	Store X register			3		4	4
STY	Store Y register			3	4		4
TAX	Transfer A to X	2
TXA	Transfer X to A	2
DEX	DEcrement X	2
INX	INcrement X	2
TAY	Transfer A to Y	2
TYA	Transfer Y to A	2
DEY	Decrement Y	2
INY	Increment Y	2
CLC	CLear Carry	2
SEC	SEt Carry	2
CLI	CLear Interrupt	2
SEI	SEt Interrupt	2
CLV	CLear oVerflow	2
CLD	CLear Decimal	2
SED	SEt Decimal	2