diff --git a/m_fdm_calc.f90 b/m_fdm_calc.f90
index 694117a..c5d11ad 100644
--- a/m_fdm_calc.f90
+++ b/m_fdm_calc.f90
@@ -594,7 +594,7 @@ module m_fdm_calc
       CALL pdfp (fbuf1,  fzzl,  fzzu,  fbuf2,  hy, xx*yy, zz, yy, 3)
       CALL pd2fp(fbuf1,  fzzl,  fzzu,  fbuf3,  hy, xx*yy, zz, yy, 3)
 
-      fbuf1(:,:,:) = r1_(:,:,:,1)                   ! rho*D
+      fbuf1(:,:,:) = r1_(:,:,:,1) * dm(:,:,:)       ! rho*D
       CALL pdfp (fbuf1,  fzzl,  fzzu,  fbuf4,  hy, xx*yy, zz, yy, 3)
 
       fbuf2 = fbuf2 * fbuf4                         ! dY/dz * d(rho*D)/dz