Pierre said:
^ I'll do it from 2006 - Neal's original comparison using the wayback machine.
Alton Towers
2006 on the day - £29.50
2006 internet - £23.00
2013 on the day - £46.20 (57% increase)
2013 internet - £34.65 (51% increase)
Thorpe Park
2006 on the day - £28.50
2006 internet - £23.00
2013 on the day - £45.60 (60% increase)
2013 online - £24.99 (9% increase)
Chessington
2006 on the day - £29.00
2006 internet - £27.00
2013 on the day - £43.20 (48% increase)
2013 internet - £32.40 (20% increase)
Drayton Manor (no online discount in 2006)
2006 - £20.95 for peak times (school holidays/weekends)
2013 on the day - £36.00 (72% increase)
2013 internet - £20.00 (5% decrease)
Flamingo Land (no online discount in 2006)
2006 - £19.00
2013 on the day - £30.00 (58% increase)
2013 internet - £27.00 (42% increase)
Tussauds/Merlin Annual Pass
2007 (no data on wayback for 2006) new - £95.00
2007 renewal - £75.00
2013 standard online - £143.00 (51% increase)
2013 standard on the day - £159.00 (67% increase)
2013 premium online - £176.00 (85% increase)
2013 premium on the day - £195.00 (105% increase)
2013 renewal (standard) - £111.00 (48% increase)
2013 renewal (premium) - £137.00 (83% increase)
So there we have it - its the Annual Pass price that's always annoyed me, things have changed as in whats included however you could argue that the new attractions that come in weren't much of a substitute for the ones that departed (the european parks). Also the fact there was one pass that included everything in 2007 whereas in 2013 the standard pass doesn't include free parking and also restricts certain dates.
For parks standard entries they're all around the 50-60% increase so its hard to criticise one park for price increases not going with the rate of inflation.
I've just noticed Flamingo Lands on the day ticket price for 2015 and was horrified. It prompted me to look at others and revisit this post...
2015 Prices
Percentage increases based on 2013 prices....
Alton Towers
On the day £50.40 (9.1% increase)
2-6 Days in advance £45.36 (30.1% increase)
7+ Days in advance £37.80 (9.1% increase)
Thorpe Park
On the day £49.99 (9.6% increase)
Advance weekend £29.99 (20% increase)
Advance midweek £24.99 (no change)
Chessington
On the day £46.00 (6.5% increase)
1-4 Days in advance £31.00 (4.3%
decrease)
5+ Days in advance £26.00 (19.75%
decrease)
Advance tickets have a rainy day guarantee, allowing guests to come back for free if it rains for more than one hour
Drayton
On the day £36.00 (no change)
1-7 Days in advance £25.00 (25% increase)
7+ Days in advance £20.00 (no change)
Flamingo Land
On the day £37.00 (23.3% increase)
Advance £31.00 (14.8% increase)
Annual Pass
2015 Standard Online £169.00 (18.19% increase)
2015 Premium Online £209.00 (18.75% increase)
2015 Standard Online Renewal £129.00 (16.21% increase)
2015 Premium Onlline Renewal £159.00 (16.06% increase)