The compression rate of onboard EIS data may vary depending on a few factors such as the observing target (QS, AR, CH, etc), slit/slot selection, exposures, etc. The purpose of this study is trying to discover how different compression schemes effect EIS data volume onboard and work out a better estimation of compression rate for compression scheme (eg. DPCM, JPEG98, JPEG95, etc.) [{Image src='images/factor/75/JPEG75_only.gif'}] QS QS,DC QS,SYN QS,CH QS,NET QS,DC,XBP QS,SYN,DC QS,DC,SEI QS,PCH XBP,QS AR AR,LMB AR,EFR AR,PLG AR,CH AR,NFL AR,CH,LMB SYN SYN,DC SYN,QS,DC PCH PCH,LMB,JET PCH,JET JET,LMB,PCH LMB LMB,LO LMB,PCH,SPI LMB,SPI ENG,LMB,JET,PCH ENG,QS,DC SYN,DC,QS SYN,DC CH CH,JET CH,XBP CH,DC CH,LMB CH,QS CH,XBP,JET,EFR CH,BP,JET PR PR,LMB PP,PCH SPI,LMB EFR SEI,EFR DC DC,LMB WAV NET SPI SPI,CH BP,CH,JET BP,JET FIL,PR FIL,QS