To use some sources you will need a NAICS or SIC code for your industry.
North American Industry Classification System
The NAIC System assigns numerical codes to industries from two to six digits. Shorter codes represent broader industry sectors. Be sure to read the full description of the NAICS code, as it may include a broader array of products/services than you might assume.
Standard Industrial Classification Manual (at OSHA site)
The SIC system assigns numerical codes to industries from two to four digits. Shorter codes represent broader industry sectors. Be sure to read the full description of the SIC code, as it often includes a broader array of products/services than you might assume.
*You will need to read explanatory materials in front/back of volumes to understand these numbers.
These sources provide ratios and financial norms commonly used in evaluating corporate financial performance within specific industries. Data varies from source to source due to different data sources, company size breakdowns, industry classification systems, and which factors are analyzed.
RMA is the most popular of these sources, but it doesn't include every industry. If your industry isn't included in RMA, you might want to try Industry Norms and Key Business Ratios, which is also a high quality source--unfortunately, we only have this in print form at the library. SME Benchmarking Tool and First Research Reports have less information--but they may include industries not in the other sources.
You may need to first find a NAICS or SIC industry code to use these sources.
*You will need to read explanatory materials at web sites to understand these numbers.