Here is table some data from 2015 thru Jun. If you look at the last 4 years, THB is climbing up. However, it is somewhat manipulated and it should trade around 35 THB against 1 USD as an average
Year
High (THB/USD)
Low (THB/USD)
Average (THB/USD)
2015
36.087
32.346
34.248
2016
36.193
34.298
35.297
2017
35.297
32.614
33.940
2018
33.714
31.183
32.310
2019
32.153
29.747
31.046
2020
32.311
29.723
31.295
2021
34.026
29.806
31.980
2022
38.234
31.406
35.078
2023
37.162
33.706
34.924
2024
37.237
33.996
34.090
2025
34.8991
32.3446
33.5024 (Jan–Jun)