Salesforce Opportunity Roll-Up

Roll-Up summary field is a nice feature in Salesforce to summary data from child record to parent within Master-Detail relationship object.

Although, Account and Opportunity is standard Salesforce object, but we can set Roll-Up summary for many purposes.

Date of last won deal
We can easily know and display when closed won opportunity in Account page layout without complex triggers.
Create roll-up summary field in Account with
- Summarized Object = Opportunity
- Field to Aggregate = Opportunity: Close Date
- Filter Criteria = Won EQUALS True
- Summary Type = MAX

Number of Opportunities

Display number of opportunities in Account page layout

Create roll-up summary field in Account with
- Summarized Object = Opportunity
- Filter Criteria =
- Summary Type = COUNT

Number of Won Opportunities

Display number of won opportunities in Account page layout

Create roll-up summary field in Account with
- Summarized Object = Opportunity
- Filter Criteria = Won EQUALS True
- Summary Type = COUNT

Total Amount of Won Opportunities
Display total amount of won opportunities in Account page layout

Create roll-up summary field in Account with
- Summarized Object = Opportunity
- Field to Aggregate = Opportunity: Amount
- Filter Criteria = Won EQUALS True
- Summary Type = SUM

Win Percentage
Display percentage of closed won opportunity for account
Create formula field with return type = Percent, with 2 decimal place
Formula = IF(Count_of_Opportunities__c > 0, Count_Won_Opportunities__c / Count_of_Opportunities__c,0)

For more information on Roll-Up Summary, click here for Salesforce documentation.