diff --git a/erpnext/accounts/report/gross_profit/gross_profit.js b/erpnext/accounts/report/gross_profit/gross_profit.js
index 685f2d6..c8a9a22 100644
--- a/erpnext/accounts/report/gross_profit/gross_profit.js
+++ b/erpnext/accounts/report/gross_profit/gross_profit.js
@@ -8,20 +8,22 @@
 			"label": __("Company"),
 			"fieldtype": "Link",
 			"options": "Company",
-			"reqd": 1,
-			"default": frappe.defaults.get_user_default("Company")
+			"default": frappe.defaults.get_user_default("Company"),
+			"reqd": 1
 		},
 		{
 			"fieldname":"from_date",
 			"label": __("From Date"),
 			"fieldtype": "Date",
-			"default": frappe.defaults.get_user_default("year_start_date")
+			"default": frappe.defaults.get_user_default("year_start_date"),
+			"reqd": 1
 		},
 		{
 			"fieldname":"to_date",
 			"label": __("To Date"),
 			"fieldtype": "Date",
-			"default": frappe.defaults.get_user_default("year_end_date")
+			"default": frappe.defaults.get_user_default("year_end_date"),
+			"reqd": 1
 		},
 		{
 			"fieldname":"sales_invoice",
diff --git a/erpnext/accounts/report/gross_profit/gross_profit.py b/erpnext/accounts/report/gross_profit/gross_profit.py
index 84effc0..225b7c6 100644
--- a/erpnext/accounts/report/gross_profit/gross_profit.py
+++ b/erpnext/accounts/report/gross_profit/gross_profit.py
@@ -369,20 +369,37 @@
 		return self.average_buying_rate[item_code]
 
 	def get_last_purchase_rate(self, item_code, row):
-		condition = ''
-		if row.project:
-			condition += " AND a.project=%s" % (frappe.db.escape(row.project))
-		elif row.cost_center:
-			condition += " AND a.cost_center=%s" % (frappe.db.escape(row.cost_center))
-		if self.filters.to_date:
-			condition += " AND modified='%s'" % (self.filters.to_date)
+		purchase_invoice = frappe.qb.DocType("Purchase Invoice")
+		purchase_invoice_item = frappe.qb.DocType("Purchase Invoice Item")
 
-		last_purchase_rate = frappe.db.sql("""
-		select (a.base_rate / a.conversion_factor)
-		from `tabPurchase Invoice Item` a
-		where a.item_code = %s and a.docstatus=1
-		{0}
-		order by a.modified desc limit 1""".format(condition), item_code)
+		query = (frappe.qb.from_(purchase_invoice_item)
+			.inner_join(
+				purchase_invoice
+			).on(
+				purchase_invoice.name == purchase_invoice_item.parent
+			).select(
+				purchase_invoice_item.base_rate / purchase_invoice_item.conversion_factor
+			).where(
+				purchase_invoice.docstatus == 1
+			).where(
+				purchase_invoice.posting_date <= self.filters.to_date
+			).where(
+				purchase_invoice_item.item_code == item_code
+			))
+
+		if row.project:
+			query.where(
+				purchase_invoice_item.item_code == row.project
+			)
+
+		if row.cost_center:
+			query.where(
+				purchase_invoice_item.cost_center == row.cost_center
+			)
+
+		query.orderby(purchase_invoice.posting_date, order=frappe.qb.desc)
+		query.limit(1)
+		last_purchase_rate = query.run()
 
 		return flt(last_purchase_rate[0][0]) if last_purchase_rate else 0