Analysis of the Systematic Errors of CCD-observations of Asteroids Performed in 2007-2008 . ... Analysis of systematic errors based on CCD-observations taken with Normal Astrograph (D/F = 0.33 m/3.5 m, FOV = 18 16 arcmin, scale = 1 arcsec/pix) of Pulkovo observatory during 2007-2008 has been made. ... A statistical approach that used mean (O-C) values obtained for positions of reference stars within the field of view separated on square bins and magnitude ranges was applied. ...