so if a dynamic cell i will have a value like 3 or 4 or 5 etc.

and the formula will get the average of the "Last 3 Mondays" or "Last 4 Mondays" etc. And to further annoy you, the dates are not in exact sequential order, some weeks the Monday is missing. so formula needs to be able to "find" the last n 'Mondays' regardless of how many rows back they are. thanks if you can assist

81 | Saturday |

4 | Monday |

94 | Tuesday |

161 | Wednesday |

143 | Thursday |

155 | Friday |

145 | Saturday |

7 | Monday |

88 | Tuesday |

133 | Wednesday |

140 | Thursday |

144 | Friday |

146 | Saturday |

16 | Monday |

16 | Tuesday |

188 | Wednesday |

148 | Thursday |

145 | Friday |

135 | Saturday |

9 | Monday |

118 | Tuesday |

160 | Wednesday |

142 | Thursday |

156 | Friday |

133 | Saturday |

7 | Monday |

84 | Tuesday |

120 | Wednesday |

160 | Thursday |

200 | Friday |

170 | Saturday |

5 | Monday |

122 | Tuesday |

138 | Wednesday |

128 | Thursday |

169 | Friday |

147 | Saturday |

57 | Monday |