求高手帮忙看看这个代码如何优化，运行太慢了

Sub wb()
Application.ScreenUpdating = False '禁止屏幕刷新
Application.Calculation = xlCalculationManual '计算模式为手动
Dim URL As String
Dim http
URL = Range("ab4")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac4") = http.responseText
URL = Range("ab5")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("AC5") = http.responseText
URL = Range("ab6")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac6") = http.responseText
URL = Range("ab7")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac7") = http.responseText
URL = Range("ab8")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac8") = http.responseText
URL = Range("ab9")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac9") = http.responseText
URL = Range("ab11")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac11") = http.responseText
URL = Range("ab12")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac12") = http.responseText
URL = Range("ab13")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac13") = http.responseText
URL = Range("ab14")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac14") = http.responseText
URL = Range("ab15")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac15") = http.responseText
URL = Range("ab16")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Ac16") = http.responseText
URL = Range("ai4")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj4") = http.responseText
URL = Range("ai5")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj5") = http.responseText
URL = Range("ai6")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj6") = http.responseText
URL = Range("ai7")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj7") = http.responseText
URL = Range("ai8")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj8") = http.responseText
URL = Range("ai9")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj9") = http.responseText
URL = Range("ai11")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj11") = http.responseText
URL = Range("ai12")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj12") = http.responseText
URL = Range("ai13")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj13") = http.responseText
URL = Range("ai14")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj14") = http.responseText
URL = Range("ai15")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj15") = http.responseText
URL = Range("ai16")
Set http = CreateObject("Microsoft.XMLHTTP")
http.Open "GET", URL, False
http.send ""
Range("Aj16") = http.responseText
Range("U1").Select
Selection.Delete Shift:=xlToLeft
Application.Calculation = xlCalculationAutomatic
Application.ScreenUpdating = True
End Sub