Constituency number changes

2007 electoral regions

With the constitutional amendments, different formula for the number of seat in parliament given by a party list vs. the number of directly elected constituency MPs were discussed. In the 2007 election, it had 400 constituencies and another 80 party list, which were calculated for 8 separate regions. The ratios in discussion now were either a 400:100 ratio or the now preferred 375:125 ratio, as well as a few others but all with either 375 or 400 constituency. Of course such changes directly prompt criticism of adjusting the law to fit party interests, which due to the better performance of the Democratic Party in the party list votes is not totally baseless. However, for the number of constituencies these are spread to the provinces according to a simple formula, so here only minor preferences for one party should be expected.

Since I already programmed the algorithm for calculating the number of constituencies per province, it's easy for me to compare the two proposed numbers. The only thing I had to program for an easier comparison was to sum up the numbers for regions. To keep the table short I have only used the simple regions as defined by the National Statistics Office, with the northern region already starting at Nakhon Sawan.

	South	Central	Northeast	North
375	52	128	126	69
	13.9%	34.1%	33.6%	18.4%
400	57	133	134	76
	14.3	33.3%	33.5%	19.0%

As one can see, the Northeast looses most constituencies in the reduction from 400 to 375, but that's of course simply to due the fact that this area has so many constituencies. So to really compare, one should check the percentage values, which show that the South and especially the North loose, while the Central wins. I have done the calculation with the population numbers as of January 1 2009.

The weight of each vote depends on the province, due to the fact that constituencies have to be within one province there's inevitably quite some inequality - whereas in Ang Thong there are 142403 citizen per MP, in Nakhon Nayok the number is 251683 (calculated for 375 constituency MPs). With 400 constituency MPs, Nakhon Nayok would instead be nearly at the top of the list with 125841 citizen per MP, as it is one of the provinces which loose a constituency in the reduction of numbers.

While all reports focus on the numbers only, none mentions whether the electoral regions will be kept or dropped with the amendments. The new value of 125 could only be divided into 5 regions, so there has to be a change in these regions for sure. The lack of mentioning them in the news makes me think they will be dropped altogether. But guess I will only know for sure after the amendments are accepted in a joint meeting of house of representatives and senate on February 11th.