The economy has not improved. It has gotten worse, if anything.

[WilliamTaft]

The economy has not improved. It has gotten worse, if anything.

Source: The Britannica Dictionary

What's the difference if I omit "if anything?"

 

[jutfrank]

The phrase if anything is used to say that you could make an argument that not only refutes, but also goes in direct opposition to a prior claim or statement.

The economy has improved. [claim]
The economy has not improved. [refutation]
It has gotten worse if anything. [going beyond refutation into a directly opposite claim]

 

[Rover_KE]

NOTE: Despite the name of this dictionary, most British English speakers use 'got' and not 'gotten' as the past participle of 'get'.

 

[probus]

However, the name Britannica Dictionary seems to be slightly misleading. According to the landing page of its website it is a dictionary of American English. Go figure.