diff --git a/images/flowchart.png b/images/flowchart.png
index 8c61976..566efd3 100644
Binary files a/images/flowchart.png and b/images/flowchart.png differ
diff --git a/index.md b/index.md
index d781874..9c20994 100644
--- a/index.md
+++ b/index.md
@@ -93,14 +93,14 @@ We incubate models across different range of policy areas. Our <a style="display
 
 <div class ="wrap">
 		<a href="https://github.com/PSLmodels/taxdata" class ="portcard">
-			<img src ="/images/taxdata.png" class="thumbnail">
+			<img src ="/images/OSPC_logo.png" class="thumbnail">
 			<div class ="container">
 				<h4><b>Tax Data</b></h4>
 				<p><i>Prepares data files used in Tax-Calculator</i></p>
 			</div>
 		</a>
                 <a href="https://github.com/PSLmodels/Tax-Calculator" class ="portcard">
-			<img src ="/images/taxcalc.jpg" class="thumbnail">
+			<img src ="/images/OSPC_logo.png" class="thumbnail">
 			<div class ="container">
 				<h4><b>Tax-Calculator</b></h4>
 				<p><i>USA federal individual income and payroll tax microsimulation model</i></p>
diff --git a/portfolio.md b/portfolio.md
index 949c7df..97f9d3b 100644
--- a/portfolio.md
+++ b/portfolio.md
@@ -218,14 +218,21 @@ a.portcard:visited {
 			</div>
 		</a>
 		<a href="https://github.com/PSLmodels/Tax-Calculator" class ="portcard">
-			<img src ="/images/taxcalc.jpg" class="thumbnail">
+			<img src ="/images/OSPC_logo.png" class="thumbnail">
 			<div class ="container">
 				<h4><b>Tax-Calculator</b></h4>
 				<p><i>USA federal individual income and payroll tax microsimulation model</i></p>
 			</div>
+		</a>
+		<a href="https://github.com/bodiyang/Taxcalc-Payroll" class ="portcard">
+			<img src ="/images/OSPC_logo.png" class="thumbnail">
+			<div class ="container">
+				<h4><b>Taxcalc-Payroll</b></h4>
+				<p><i>USA federal individual payroll tax microsimulation model</i></p>
+			</div>
 		</a>
 			<a href="https://github.com/PSLmodels/Behavioral-Responses" class ="portcard">
-			<img src ="/images/behresp.png" class="thumbnail">
+			<img src ="/images/OSPC_logo.png" class="thumbnail">
 			<div class ="container">
 				<h4><b>Tax-Calculator: Behavioral-Responses</b></h4>
 				<p><i>Estimates behavioral responses to changes in the US federal tax system</i></p>
@@ -253,7 +260,7 @@ a.portcard:visited {
 			</div>
 		</a>
 			<a href="https://github.com/PSLmodels/taxdata" class ="portcard">
-			<img src ="/images/taxdata.png" class="thumbnail">
+			<img src ="/images/OSPC_logo.png" class="thumbnail">
 			<div class ="container">
 				<h4><b>Tax Data</b></h4>
 				<p><i>Prepares data files used in Tax-Calculator</i></p>