need help-increasing/decreasing

Respected,
The display is the answer that I need to get from formula.(means just one numeral with plus or minus sign Meaning is just added to give somewhat of description.

cell   #values	#display   #meaning
b2     # 1.4			
b3     # 1.5			
b4     # 1.7	# +2       #increasing in last 2 days	
b5     # 1.8	# +3	  #increasing in last 3 days	
b6     # 1.3			
b7     # 1.2	# -2	  #decreasing in last 2 days	
b8     # 1.1	# -3	  #decreasing in last 3 days	
b9     #-0.8			
b10    #-0.6			
b11    #-0.4	#  +2	  #increasing in last 2 days	
b12    #-0.3	#  +3	  #increasing in last 3 days	
b13    #-0.6			
b14    #-0.7	# -2	  #decreasing in last 2 days	
b15    #-0.8	# -3	  #decreasing in last 3 days

Zohar