<includeonly>{{DecadesAndYears/yearbox|{{{1}}}|{{#expr:({{{4}}}-4.5)*{{#ifeq:{{{5}}}|AD|1|-1}}+{{{3}}}4.5}}|{{{2}}}|{{{5}}}}}</includeonly><noinclude>Gives the table element for the ({{{4}}}+1)th year of the {{{3}}}0s.
*{{{1}}} = namespace
*{{{2}}} = century 
*{{{3}}} = decade 
*{{{4}}} = row position
*{{{5}}} = epoch AD or BC</noinclude>