The decline in May continues the reversal that started in April, and is in line with the deterioration in manufacturing confidence seen this month from Germany, China and elsewhere.
Trade ministry figures showed output was down 1.2% in July, a steep reversal from the 0.4% rise recorded in June and way out of line with analysts expectations of a 1.7% increase.
The collection of artists believes the cuts are out of line with what's happening in the rest of the country, and asks for the reversal of what it calls a "baffling" decision.