Evaluation of text summary is very essential issue of summarization. Normally, the authors can judge the relevance of any summary by applying extrinsic or intrinsic evaluation measures. Intrinsic evaluation techniques try to judge the relevance of any summary with evaluation by human experts. Extrinsic evaluation techniques judge quality of summary with task oriented techniques like task related to extraction of information. Usually, they should must judge two attributes of any summary Compression Ratio (CR) which states up to which extent the summary is to be compressed as compared to source text and Retention Ratio (RR) which states up to which extent they have to retain the information in the summary. RR is ratio of information present in summary to the information present in source text.