l_t_range: How do I add yesterday from sy-datum to my selection?

Hi

I have the ABAP selection below in a infopackage. I would like to add sy-datum-1 ("yesterday") as well to the selection. How will I do that and is it possible to say sy-datum-1?

Thanks in advance, kind regards,

Torben

data: l_idx like sy-tabix.

read table l_t_range with key

fieldname = '/BIC/ZSY_DATE'.

l_idx = sy-tabix.

if l_t_range-low is initial and l_t_range-high is initial.

l_t_range-sign = 'I'.

l_t_range-option = 'EQ'.

l_t_range-low = sy-datum.

*....

modify l_t_range index l_idx.

endif.

p_subrc = 0.