Roman tradition had it that the god Janus was blessed with two faces - one that could see into the past, another that could look forward into the future, a gift presented to him by Saturn, god of time and age. All that had passed and all that was to pass was Janus's to observe; with hind- and foresight unblinkered, he could strike against the Roman army when they would do ill, and protect them when they fought in the interests of what was right. Sadly, our eyes look out only into the present, and though we can keep the past alive, the future remains forever shrouded in mist.

Yet though we lack the gift of seeing tomorrow as if it were today, there's no reason not to shine a light out into that mist, to discern the shadows of things to come and prepare ourselves accordingly for their coming. By understanding what's gone before and the paths that led us to where we are now, we can better foresee where the path will lead us on to, and any obstacles it may set in our way. With the right tools to examine our past, we can better comprehend our present and clear the mist of the future: the right tools can do for us what the second face did for Janus.

Juliet doesn't have two faces. She has one, the same number as most of us, and her two eyes are rather lacking in any divine gifts. Unfortunately, she could do with being able to see the future a little more clearly - her employer, Happy-Go-Lucky Toys, needs her to assess sales trends to build a picture of what the key toys will be for next Christmas. Success or failure for the company is heavily influenced by performance over that vital period, but their product strategy needs to be decided long in advance; Juliet needs to build this strategy from existing data, and Microsoft Excel gives her the tools to do just that.

Her plans will be rooted in analysing existing sales figures to identify trends. It's not enough just to run through the most recent data and see what product lines have sold the most units - she needs to identify how that data is developing, which lines are growing, accelerating, decelerating or shrinking. Conditional formatting in Excel gives her the power to identify such trends immediately and without difficulty. It can be something as simple as heat maps, using a spectrum of colours to identify which figures in a data set are improving and worsening, or symbols - traffic lights, for instance, or stars - that highlight the best and worst performers. More detail on these trends can be provided with Sparklines and data bars, small charts that fit inside a cell within the spreadsheet for an easy, at-a-glance explanation of how individual lines have been progressing.

Excel can also provide a deeper analysis, to fine tune her plans. A wide range of charts can give a clear visual insight into any aspect of the data, allowing her to form a precise picture of the areas in which the company has seen real improvement - whereas Sparklines and data bars allow her to get the gist over many different parts of the data at once, Excel charts illustrate individual elements in detail. And to see how that detail relates to the wider company, and how particular details relate to one another, Excel's PowerPivot technology allows her to construct analyses of disparate pieces of information from any data source (such as the relationship between certain lines and certain categories of customer), giving her the power to see beyond the basic figures to a full understanding of what those figures really mean for the company.

Being able to investigate the information she has at any level, studying trends and relationships for individual lines and across the board, allows Juliet to be confident that her plan for next Christmas will bring great success for Happy-Go-Lucky. Of course, Excel also makes it easy for her to share the fruits of her labours, whether as business dashboards, reports, printed content or PowerPoint presentations, so her employers can have confidence in her too. She - and anyone needing to analyse data trends and developments - could certainly benefit from a short training course to get to grips with all that Excel has to offer; looking into your data with Excel can help you to look into a brighter future for your business. And this time, no-one needs a divine gift to help them.