100GB Database size to reduce

Mabuhay!

Hi! We have this database size 100GB and we plans to reduce it to at least 60GB so it will runs more smoother. 

I recently run

CREATE TABLE #tmpTableSizes
(
    tableName varchar(100),
    numberofRows varchar(100),
    reservedSize varchar(50),
    dataSize varchar(50),
    indexSize varchar(50),
    unusedSize varchar(50)
)
insert #tmpTableSizes
EXEC sp_MSforeachtable @command1="EXEC sp_spaceused '?'"


select  * from #tmpTableSizes
order by dataSize desc

to know how much row size does our database consist of. I deleted some transactions less than and equal to Year 2014. As of today whan I look at the database size it remains 100GB still. Or do I need to back up and restore it again so it will update the database size?

Am I missing something here so I can meet much lesser database size soon.

Thanks,

Chris