As stated in Appendix A17 in IAS 36 - Impairment of Asset:
"As a starting point in making discount rate estimate, the entity might take into account the following rates:
a. the entity’s weighted average cost of capital (WACC) determined using techniques such as the Capital Asset Pricing Model;
b. the entity’s incremental borrowing rate; and
c. other market borrowing rates.
So, what is above incremental borrowing rate? and When shoul we use this instead of WACC?