This object counts CRC blocks received in error, with the E-bit set to 1, over one-second, 50-block sampling periods, providing a direct measure of the quality of the underlying 64 Kbps connection carrying the H.221 signal. Admins use the documented percentage-to-error-rate mapping, for example roughly 70% of blocks in error corresponding to an error rate near 10E-4 while 0.012% corresponds to about 10E-8, to translate this counter into a standard circuit quality figure. For example, an admin seeing a high proportion of CRC blocks in error over successive one-second samples would flag the 64 Kbps circuit as degraded and needing line testing.