For all cross sections within a region defined by the base of the shear wall and a plane at a distance

*L*above the base of the shear wall, the nominal shear strength shall be determined by Equation 21-1.

_{w} V=_{n} A _{n} ρ_{n} f_{y} | (Equation 21-1) |

The required shear strength for this region shall be calculated at a distance

*L*/2 above the base of the shear wall, but not to exceed one-half story height.

_{w }For the other region, the nominal shear strength of the shear wall shall be determined from Section 2108.