sql query substr

Hello List,  

Look into the queries below, why the result of first two queries is starting with a blank space, and to get rid of this I have to substr from position 2 rather than 1.  

select substr(to_char(34.25,'99.99'),1,5) col1 from dual; --result is
' 34.2'

select substr(to_char(-4.25,'99.99'),1,5) col1 from dual; --result is
' -4.2'

select substr(to_char(34.25,'99.99'),2,5) col1 from dual; --result is
'34.25'

select substr(to_char(-4.25,'99.99'),2,5) col1 from dual; --result is
'-4.25'
 

TIA Krishan  

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