Scopus Sourcesdoes not have complete citation information for articles published prior to 1996.
Four years of data are necessary to calculate a SJR or SNIP. Because Scopus records data starting in 1996, the first year available for a SJR or SNIP is 1999.
Scopus Sources provides a view of journal performance using Scopus citation data and includes two new journal metrics - SJR and SNIP.
Scopus Sources is accessible via Scopus from Elsevier (requires subsription).
SJR and SNIP are freely accessible.
Scopus Sources will chart:
You can compare up to 10 journals.