Is it acceptable to some extent if I use “a dramatical increase in the economy” instead of “a dramatic increase…”. I made that mistake in a speech 
Hi quan11287
Even though you might find ‘dramatical’ in some dictionaries, I would consider the usage ‘a dramatical increase’ to be wrong. An audience of native speakers of English will also immediately perceive an error if you say ‘a dramatical increase’.
You should only say ‘a dramatic increase’ (or use the verb and adverb: ‘increased dramatically’).
Amy