diff --git a/doc/OpenSTA.odt b/doc/OpenSTA.odt
index cf2d1fa6..2079b261 100644
Binary files a/doc/OpenSTA.odt and b/doc/OpenSTA.odt differ
diff --git a/liberty/LibertyExpr.cc b/liberty/LibertyExpr.cc
index 645d2b22..fb69c6e9 100644
--- a/liberty/LibertyExpr.cc
+++ b/liberty/LibertyExpr.cc
@@ -29,7 +29,9 @@ namespace sta {
 LibExprParser *libexpr_parser;
 
 FuncExpr *
-parseFuncExpr(const char *func, LibertyCell *cell, const char *error_msg,
+parseFuncExpr(const char *func,
+	      LibertyCell *cell,
+	      const char *error_msg,
 	      Report *report)
 {
   if (func != nullptr && func[0] != '\0') {
@@ -42,8 +44,10 @@ parseFuncExpr(const char *func, LibertyCell *cell, const char *error_msg,
     return nullptr;
 }
 
-LibExprParser::LibExprParser(const char *func, LibertyCell *cell,
-			     const char *error_msg, Report *report) :
+LibExprParser::LibExprParser(const char *func,
+			     LibertyCell *cell,
+			     const char *error_msg,
+			     Report *report) :
   func_(func),
   cell_(cell),
   error_msg_(error_msg),
@@ -84,7 +88,8 @@ LibExprParser::makeFuncExprNot(FuncExpr *arg)
 }
 
 FuncExpr *
-LibExprParser::makeFuncExprXor(FuncExpr *arg1, FuncExpr *arg2)
+LibExprParser::makeFuncExprXor(FuncExpr *arg1,
+			       FuncExpr *arg2)
 {
   if (arg1 && arg2)
     return FuncExpr::makeXor(arg1, arg2);
@@ -93,7 +98,8 @@ LibExprParser::makeFuncExprXor(FuncExpr *arg1, FuncExpr *arg2)
 }
 
 FuncExpr *
-LibExprParser::makeFuncExprAnd(FuncExpr *arg1, FuncExpr *arg2)
+LibExprParser::makeFuncExprAnd(FuncExpr *arg1,
+			       FuncExpr *arg2)
 {
   if (arg1 && arg2)
     return FuncExpr::makeAnd(arg1, arg2);
@@ -102,7 +108,8 @@ LibExprParser::makeFuncExprAnd(FuncExpr *arg1, FuncExpr *arg2)
 }
 
 FuncExpr *
-LibExprParser::makeFuncExprOr(FuncExpr *arg1, FuncExpr *arg2)
+LibExprParser::makeFuncExprOr(FuncExpr *arg1,
+			      FuncExpr *arg2)
 {
   if (arg1 && arg2)
     return FuncExpr::makeOr(arg1, arg2);
@@ -117,7 +124,8 @@ LibExprParser::setResult(FuncExpr *result)
 }
 
 size_t
-LibExprParser::copyInput(char *buf, size_t max_size)
+LibExprParser::copyInput(char *buf,
+			 size_t max_size)
 {
   size_t length = strlen(func_);
   if (length == 0)
diff --git a/liberty/LibertyExpr.hh b/liberty/LibertyExpr.hh
index e4faf497..7a2ae1dc 100644
--- a/liberty/LibertyExpr.hh
+++ b/liberty/LibertyExpr.hh
@@ -26,7 +26,9 @@ class LibertyCell;
 class FuncExpr;
 
 FuncExpr *
-parseFuncExpr(const char *func, LibertyCell *cell, const char *error_msg,
+parseFuncExpr(const char *func,
+	      LibertyCell *cell,
+	      const char *error_msg,
 	      Report *report);
 
 } // namespace
diff --git a/search/Power.cc b/search/Power.cc
index 335caa72..eec79f9f 100644
--- a/search/Power.cc
+++ b/search/Power.cc
@@ -505,8 +505,8 @@ Power::power(const Instance *inst,
     if (to_port->direction()->isAnyOutput())
       findSwitchingPower(cell, to_port, activity, load_cap,
 			 dcalc_ap, result);
-    findInternalPower(to_port, inst, cell, activity,
-		      inst_clk, load_cap, dcalc_ap, result);
+    findInternalPower(to_pin, to_port, inst, cell, activity,
+		      load_cap, dcalc_ap, result);
   }
   delete pin_iter;
   findLeakagePower(inst, cell, result);
@@ -528,11 +528,11 @@ Power::findInstClk(const Instance *inst)
 }
 
 void
-Power::findInternalPower(const LibertyPort *to_port,
+Power::findInternalPower(const Pin *to_pin,
+			 const LibertyPort *to_port,
 			 const Instance *inst,
 			 LibertyCell *cell,
 			 PwrActivity &to_activity,
-			 const Clock *inst_clk,
 			 float load_cap,
 			 const DcalcAnalysisPt *dcalc_ap,
 			 // Return values.
@@ -554,10 +554,9 @@ Power::findInternalPower(const LibertyPort *to_port,
     if (pwr->port() == to_port) {
       const char *related_pg_pin = pwr->relatedPgPin();
       const LibertyPort *from_port = pwr->relatedPort();
-      if (from_port == nullptr) {
+      if (from_port == nullptr)
 	// Input port internal power.
 	from_port = to_port;
-      }
       FuncExpr *when = pwr->when();
       // If all the "when" clauses exist VSS internal power is ignored.
       if ((when && internalPowerMissingWhen(cell, to_port, related_pg_pin))
@@ -570,9 +569,10 @@ Power::findInternalPower(const LibertyPort *to_port,
 	else if (search_->isClock(from_vertex))
 	  duty = 1.0;
 	else {
-	  PwrActivity from_activity = findClkedActivity(from_pin, inst_clk);
-	  float duty1 = 1.0 - (input_duty_sum - from_activity.duty());
-	  duty = from_activity.activity() * duty1 / to_activity.activity();
+	  PwrActivity from_activity = findActivity(from_pin);
+	  PwrActivity to_activity = findActivity(to_pin);
+	  float duty1 = input_duty_sum - from_activity.duty();
+	  duty = from_activity.activity() * (1.0 - duty1) / to_activity.activity();
 	}
 	float port_energy = 0.0;
 	TransRiseFallIterator tr_iter;
@@ -624,7 +624,7 @@ Power::internalPowerMissingWhen(LibertyCell *cell,
     auto when = pwr->when();
     if (pwr->port() == to_port
 	&& pwr->relatedPort() == nullptr
-	&& stringEq(pwr->relatedPgPin(), related_pg_pin)
+	&& stringEqIf(pwr->relatedPgPin(), related_pg_pin)
 	&& when) {
       when_count++;
       when_input_count = funcExprPortCount(when);
diff --git a/search/Power.hh b/search/Power.hh
index 6c1513fe..8321ceb5 100644
--- a/search/Power.hh
+++ b/search/Power.hh
@@ -107,11 +107,11 @@ protected:
 	     const Corner *corner,
 	     // Return values.
 	     PowerResult &result);
-  void findInternalPower(const LibertyPort *to_port,
+  void findInternalPower(const Pin *to_pin,
+			 const LibertyPort *to_port,
 			 const Instance *inst,
 			 LibertyCell *cell,
 			 PwrActivity &to_activity,
-			 const Clock *inst_clk,
 			 float load_cap,
 			 const DcalcAnalysisPt *dcalc_ap,
 			 // Return values.