Factory gate prices fell 0.4 per cent between March and April, with annual figures falling further.
The data from the Central Statistics Office showed the annual decline widened in the year to April, from 3.3 per cent recorded in March to 3.8 per cent in April.
The price index for export sales fell by 0.7 per cent on a monthly basis in April, and the index for home sales rose by 1.4 per cent.
On a yearly basis, the decline moved to 3.8 per cent for export sales, a figure that can be influenced by fluctuating exchange rates, while the home sales showed a 4.1 per cent fall.